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Kashmir traditionally known as heaven on earth for its beauty is gifted with water resources comprising rivers, lakes, streams and springs. Lakes provide a multitude of uses and are prime regions of human settlement and habitat. One such water body is Khushalsar Lake located in the downtown area of Srinagar city. It is noticed that Khushalsar at present has fallen victim to extensive encroachment, garbage dumping and the release of untreated sewage. Taking the pathetic condition of this lake and dynamic nature of water bodies in general into consideration this study was taken up to analyse the different physicochemical parameters and the rotifer abundance of this water body since rotifers are considered to be important indicators of trophic conditions of any aquatic habitat. The data collected was analysed using standard tools, statistical software’s SPSS (version 20) and PAST3. Nutrient content of this water body was found to be high and only sixteen species of Rotifera were observed. Statistically different physico-chemical parameters were compared at inlet, middle and outlet of the study lake. Only few parameters showed significant differences. Shannon-Wiener index of rotifer signifies the water body to be moderately diverse as the values lies below 5.00 while as values of Simpson diversity index indicate accelerated eutrophication.

type:Journal Article, Recombinant Escherichia coli JM109 harbouring the polyhydroxyalkanoate (PHA) biosynthesis gene (phaCABco) of Comamonas sp. EB172, an acid tolerant microbe, was examined for the production of PHAs from various carbon sources. The study demonstrated that the recombinant E. coli JM109 had the potential to utilize both sugar- and acid-based carbon sources, for the biosynthesis of both poly(3-hydroxybutyrate) P(3HB) and poly(3- hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) copolymers. In the shake flask experiments, the strain was capable of producing P (3HB-co-3HV) copolymer from mixed organic acids, and higher productivities were obtained using glucose compared to mixed acids. However, PHA accumulation was found to be similar, regardless of the carbon source used. Nitrogen supplementation in the medium was found to improve the cell dry weight, but negatively affected the 3HV formation in copolymer production. Maximum 3HV monomer (3 mol%) was obtained with C/N 42.1, using mixed acids as the carbon source. In the 2L bioreactor, the productivity and yield based on substrate utilization coefficient were found to be 0.16 g PHA/(L.h) and 0.41 g PHA/g substrate under C/N around 75, using 20 g/L glucose and 0.5 g/L ammonium sulphate, respectively. The polymer produced by the recombinant strain had molecular weight in the range of 8.5 x 105 to 1.4 x 106 Da. Overall, the ability of the recombinant E. coli JM109 to utilize both glucose and mixed acids, has widened its substrate selection for fermentation, including the opportunity to use renewable biomass

In the process of infection by the Baculovlrus, the haemocytes of Oryctes rhinoceros were found to undergo changes in the total and differential counts. Of the five classes of haemocytes, the granular cells and the plasmatocytes exhibited changes in population levels. In advanced stages of infection, there was selective depletion of plasmatocytes.

Determining effective management strategies for species and environments threatened by climate change depends on accurate predictions about how environments will change and how species within them will respond to those changes. Small scale local studies investigating all factors that correlate with differences in population sizes of target species are an essential first step in identifying factors that currently constrain distribution. This understanding can be extended by overviewing records of target species that have been kept under different, non-natural conditions, as well as by considering pre-modern environmental conditions that supported ancestral populations of the target species. Understanding modern as well as pre-modern correlations of this kind will increase capacity to develop conservation strategies to optimise survival of threatened species. This thesis provides new understanding about correlates of this kind in relation to the endangered Australian marsupial, the Mountain Pygmy-possum, Burramys parvus. Restricted in distribution to small populations on isolated mountaintops and surrounded by hard limit dispersal barriers, B. parvus cannot escape debilitating changes anticipated to result from climate change. The palaeoecological records for the lineage are reviewed, as are early captive breeding records for the living species kept under a range of different artificial conditions. The restricted nature of the modern distribution of B. parvus, as previously understood, has been demonstrated to be a misleading indication of its physiological resilience. Significantly, B. parvus has been found to occur outside of its predicted bioclimatic range in areas which received, contrary to previous presumption, little to no snow cover. Long term patterns in demography were used to reassess habitat variables. Variables associated with high and medium quality habitats were quantified. The presence of a permanent watercourse (blockstream) at occupied boulderfields

Anaplasmosis, also known as yellow fever, is an infectious parasitic disease of cattle caused by the protozoan Anaplasma marginale. Anaplasma marginale infects the erythrocytes and causes severe anaemia, weakness, loss of appetite, fever, depression, abortion, decreased milk production, constipation, jaundice and sometimes death. In Malaysia, data on A. marginale infection is still behind compared to other parasites such as nematodes. Anaplasmosis in livestock has received little attention in Malaysia with only occasional reports in cattle. In addition, the determinants of tick- and fly-borne transmission are not well understood. Looking into this possibility, this study was carried out to investigate and to compare the prevalence rate of bovine anaplasmosis in Malaysia. A seroprevalence study on bovine anaplasmosis was conducted at the Veterinary Research Institute, Malaysia. Sera of various cattle breeds were collected from farms and abattoirs to be tested for the presence of A. marginale. Competitive enzyme-linked immunosorbent assay (c-ELISA) Anaplasma antibody test kits by VMRD, Inc. were used for this study, where antibodies to A. marginale from sample sera inhibit the binding of horseradish peroxidase (HRP)-labelled monoclonal antibody to the Anaplasma antigen coated on the plastic wells. A total number of 267 serum samples were tested and 79.4% were positive for bovine anaplasmosis. Results showed that the infection percentage is 100% in Pahang while the state with lowest infection percentage is Sabah with 59.2%. A comparison is done between Peninsular Malaysia with Sabah and Sarawak. The infection percentage in Peninsular Malaysia is higher at 87% while Sabah and Sarawak has an infection percentage of 60%. However, there is no significant difference in the rate of infections. The high number of cases in Peninsular Malaysia may be caused by the lack of strict control measures due to dependence on modern tools and drugs, while cases in Sabah and Sarawak may b

The recent increase in drug-resistance bacteria has become a very serious threat to the treatment of infectious diseases. Over recent decades, a growing numbers of literatures have validated the application of bacteriophages for therapy against antibiotic-resistance bacteria. With rapid dissemination of these resistant bacteria pathogens, the interest in alternative remedies to antibiotics using bacteriophages therapy is gaining new ground. Based on the recent studies of bacteriophage applications against bacterial infections in countries where this alternative therapy has been approved, many scientists and companies believed that phages have the ability to treat and prevent diseases caused by bacteria. Malaysia, being well known as one of the mega diverse countries could promise the potential new phages that could be applied in phage therapy. The overall objectives of this research including isolation and purification of potentially new phages from environments, characterization of the isolated phages based on morphological study, physicochemical attributes, genomic and proteomic analysis. Lastly, the isolated phages would be developed into phage therapy against bacterial infection through in vitro and in vivo test. Preliminary results presented here, show a total of four phages were successfully isolated from human waste. Two of the phages were successfully isolated infecting Proteus mirabilis that caused urinary tract infection in human whereas another two phages infecting Escherichia coli 0157:H7 (caused food-borne diseases) and Escherichia coli ATCC 13706, respectively.

Cryopreservation techniques using PVS2 vitrification was applied on PLBs of Dendrobium Bobby Messina, with survival monitored through observations of growth rate and the 2,3,5-triphenyltetrazolium chloride (TTC) analyses. The parameters optimized were PLBs size, preculture concentration, preculture duration, PVS2 incubation temperature and duration. The optimized parameters obtained were 3-4mm of PLBs precultured in 0.2M sucrose for 1 day, treated with a mixture of 2M glycerol and 0.4M sucrose supplemented with half strength liquid MS media at 25°C for 20 minutes and subsequently dehydrated with plant vitrification solution 2 (PVS2) at 0°C for 20 minutes prior storage in liquid nitrogen. Following rapid warming in a water bath at 40°C for 90 seconds, PLBs were washed with a half strength liquid MS media supplemented with 1.2M sucrose. Subsequently, PLBs were cultured on half strength semi-solid MS media supplemented with 2% (w/v) sucrose in the absence of growth regulator. The optimized vitrification method was successful in preserving this orchid as it produced growth recovery in cryopreserved PLBs up to 40%. Ascorbic acid was added in the media to evaluate the regeneration process of cryopreserved PLBs. However, growth recovery rate was only 10% at 0.6mM ascorbic acid. RAPD analysis using 6 primers indicated that cryopreserved and non-cryopreserved PLBs from vitrification method were genetically faithful to the mother plant. However, 3 primers showed polymorphism and 1 primers indicated partial polymorphism between the cryopreserved and non-cryopreserved PLBs in comparative to the mother plant.

Much of the fundamental understanding of microbial physiology is based onlaboratory studies of freely suspended cells. While these studies have been essentialfor our foundational understanding of the genetics, physiology and behavior ofmicrobes, it is now recognized that a majority of bacterial cells in nature exist inbiofilms [1] associated with surfaces or as floating cell aggregates. In fact, it hasrecently been proposed that microbial communities originally developed on surfaces,including the first bacterial and archael cells, and that the planktonic cell phenotypeevolved as a dispersal mechanism [2]. Hallmarks of cells residing in biofilmcommunities are increased metabolic efficiency [3] as well as increased resistanceto environmental stresses such as desiccation, ultraviolet radiation and oxidativestress [4–6]. This correlation has dramatic consequences as residing in aggregateshas been shown to confer increased resistance of bacterial cells also to biocides suchas antibiotics, disinfectants and detergents [7–9]. In addition, once established, thesebiofilms are able to resist invasion by other organisms and predation by protozoans innature or host immune cells in the human body [5,6,10]. This is especially problematicas it is also recognized that the majority of bacterial infections involve biofilms[11]. The recent explosion of research in the field of biofilm biology has led to anenhanced appreciation for the multicellular aspects of microbiology and has resultedin the general acceptance of a model of the biofilm mode of life.Pseudomonas aeruginosa has become a model organism for the study of biofilmsdue to its metabolic versatility and variability in its response to environmental signals,which promotes successful colonization of different habitats and growth undervarying environmental conditions [12,13]. This ability is likely a reflection of its largegenome, allowing for metabolic plasticity and quick responses to varying stimuli.P. aeruginosa is also a hum

Oviposition preferences of three major identified parasitoids; Ooencyrtus erionotae Ferrière (Hymenoptera, Encyrtidae), Cotesia erionotae (Wilkinson) (Hymenoptera, Braconidae) and Brachymeria albotibialis (Ashmead) (Hymenoptera, Chalcididae) of Erionota thrax (L.) (Lepidoptera: Hersperiidae) eggs, larvae and pupae respectively were studied in the laboratory and field during a high-density period of the pest. Egg stage I (newly laid), stage 2 (intermediate), and stage 3 (advanced) were susceptible to O. erionotae oviposition. Stage 3 was the most preferred egg host with a mean of 3.4 adult parasitoids emerging per egg. For C. erionotae, second, third, and fourth larval instars were susceptible. The third instar larva was the most preferred stage for oviposition with a mean of 87 adult parasitoids emerging per larva. For B. albotibialis, only prepupae and pupae were susceptible. The pupa was the most preferred host stage with mean of 7.1 adult parasitoids emerging per pupa. In the case of O. erionotae and C. erionotae, no super-parasitism or multi-parasitism was observed.

–The objective of the present study was to determine the best concentration of urea solution and rinsing time to remove adhesiveness of African catfish eggs. Four different concentrations of rinse solution were used in this experiment comprising of 2 g, 4 g, 6 g and 8 g of urea diluted in 4 g NaCl/L of water producing a concentration of 0.486 mM, 0.973 mM, 1.458 mM, and 1.946 mM of urea concentration respectively, while 4 g NaCl/L of water without urea were used as control. The fish eggs were rinsed with the solutions at different durations namely; 1, 5 and 10 minutes. Each rinsing solution concentration and rinsing time were conducted in three replicates. The fertilization and hatching rates increased and peaked from the control (0 mM of urea) to 0.466 mN urea and decreased when concentration of urea was increased to 0.973 mM urea and 1.458 mM urea, then increased again at 1.946 mM urea, but these values were lower than at 0.486 mM urea. Thus, the best concentration for fertilization and hatching rates were 0.486 urea of urea. However 0.973 mM of urea was optimum in reducing clumping of eggs. Keywords: Clumping; Fertilization; Hatching; Brood fish

[Abstract not available]

The present study was intended to evaluate the various pharmacognostical procedures in the leaves of E. hirta, (Euphorbiaceae). The various pharmacognostical parameters were carried out as per WHO guidelines procedure i.e., macroscopic and microscopic evaluation, heavy metal analysis, functional group analysis by Fourier Transform Infrared (FTIR) spectroscopy and assay. The study was extended with analyzing the chemical compounds identification in the extract of E. hirta by using GC-MS. The assay part of standardization involved determination of the antioxidant activity (DPPH assay) which could help assesses the chemical effects and establishes curative values. The extracts showed an antioxidant activity above 50%, independent of the extraction time. Six major peaks in the range of 600 - 1500 and 2800 - 3400 cm-1 were observed in the FTIR spectra. The chemical constituent aspect of standardization involves quantification of the main chemical components in E. hirta. The GC-MS method used for quantification of 1,3,4,5-tetrahydroxycyclohexanecarboxylic acid in the extract was rapid, accurate, precise, linear (R2 = 0.9981), rugged and robust. The concentrations of heavy metals determined in E. hirta extract are well below the permissible limit. The result of the pharmacognostical standardization of this plant serves as a reference piece and helps in future identification and authentication of this plant specimen.

Dispersal costs can be classified into energetic, time, risk and opportunity costs and may be levied directly or deferred during departure, transfer and settlement. They may equally be incurred during life stages before the actual dispersal event through investments in special morphologies. Because costs will eventually determine the performance of dispersing individuals and the evolution of dispersal, we here provide an extensive review on the different cost types that occur during dispersal in a wide array of organisms, ranging from micro-organisms to plants, invertebrates and vertebrates. In general, costs of transfer have been more widely documented in actively dispersing organisms, in contrast to a greater focus on costs during departure and settlement in plants and animals with a passive transfer phase. Costs related to the development of specific dispersal attributes appear to be much more prominent than previously accepted. Because costs induce trade-offs, they give rise to covariation between dispersal and other life-history traits at different scales of organismal organisation. The consequences of (i) the presence and magnitude of different costs during different phases of the dispersal process, and (ii) their internal organisation through covariation with other life-history traits, are synthesised with respect to potential consequences for species conservation and the need for development of a new generation of spatial simulation models. © 2011 The Authors. Biological Reviews © 2011 Cambridge Philosophical Society.

A research was conducted to study the effect of different parts of the extracts from Curculigo latifolia Dryand plant. They were from the roots, stems and leaves by using methanol as the extraction solvent. The antimicrobial activity of methanol extract from Curculigo latifolia Dryand was then performed on various tested bacteria, yeasts and fungi. The results revealed that the extracts possessed antimicrobial activities on all of tested bacteria and yeasts. However, all the tested fungi exhibited resistant against all the different parts of Curculigo latifolia Dryand extracts. The minimum inhibitory concentration (MIC) and minimum lethality concentration (MLC) of the Curculigo latifolia Dryand extracts against bacteria and yeast cells were determined and the mode of action of the roots extract on the cells was studied by means of microscopy

The term mangrove may refer to an ecosystem or individual plants where the distribution of woody plants usually influenced by climate, water salinity, tides, type of soil in the mangrove swamps and environmental activities including development, housing and industrial. Thus only a certain species that can survive under this extreme condition. A study had been conducted in Byram Permanent Mangrove Forest Reserve to provide baseline information on the distribution pattern of plant growth in mangrove area. The main objective of this study is to determine the composition and the distribution pattern of true-mangrove woody plant species. To assess the species composition, the forest reserve nearest to the sea, which run approximately 2.0 km, parallel to the sea, was divided into three main sections (i.e. 600 m each section with a minimum 50 m wide border between the sections). Species enumeration was conducted in 11 plots, where each plot size is 10m x 10m. In general these plots were established in random stratified manner, from the sea towards the terrestrial part of the mangrove forest. In total, we recorded 290 of individual woody plants. The most abundant species in term of occurrences within all zones and forest section is Bruguiera parvifolia.

Malathion and Fendona® (alphacypermethrin) insecticides were tested against larvae and adult stages of house flies, Musca domestica Linnaeus. The percentage mortality of House flies larvae range between 0% and 100%at different exposed dose rate of tested insecticide. Probit analysis was used to determine the LD50. The value LD50 for malathion without food medium was 0.833 -l/larvae and treatment with food medium was 0.895 -l/larvaerespectively. The LD50 for Fendona® without food medium was 0.545 -l/larvae and 0.870 -l/larvae for treatment with food medium. The LD50 values for Fendona® in both treatment was lowers compared with malathion, which meansthat alphacypermethrin is more toxic than malathion. Different with the test on adult house flies, the knockdown time values for alphacypermethrin at KT50 is 9.876 minutes and KT95 is 20.495 minutes against female adult house fliesand were significantly lower than malathion (KT50 is 75.17 minutes and KT95 is 103.38 minutes respectively). Result also showed that a total of 1.0-l of Fendona® is reacting more effective than 1.0-l of malathion. Therefore, we canconclude that Fendona® is the most effective insecticide towards larvae and adult stage of M. domestica. The effectiveness of both chemicals was affected when treated larvae was in the rearing medium

This study was specified in documenting Mimosa reaction in the state of defoliation on the plants. As defoliation was believed to cause plants experiencing both positive and/or negative effects on its growth performance, thus among the aim of this study is to monitor the emergence of foliar buds in respond with vary level of defoliation intensities. The seedlings were grown singly in polybags up to four leaf stage as. Grown seedlings were randomly subjected under four different defoliation intensities: control (un-defoliated), 25%, 50%, and 100% in which 10 replicates of seedling for each treatment. Experiment was ceased at the 6th month after establishment of plants grew. Results shown that, the effect of defoliation on the production of foliar buds was significantly difference between the treatments (P< 0.05). As compared with 25%, 50% and 100% defoliation, un-defoliated plants showed the highest amount of foliar buds production which is 14 buds. While, there were no differences amount of foliar buds production between 25% and 50% defoliation with 5 foliar buds per plants. Emergence of foliar buds was reportedly lowest in 100% defoliation plant when there were no sign of buds emergence. Results concluded that, the subjected plants of control, 25% and 50% leaves defoliation treatments, were able to performed tolerance effect relative to the induced stressor. Apart from that, experiment revealed that the 100% defoliation has probability of detrimental effect on growth and reproduction of Mimosa seedling as it hindrance the germination of foliar buds.

Two potential substrates namely rice bran and unprocessed brown rice indicated positive result of lovastatin existence. Aspergillus niger SAR I, our local isolated fungus, took a responsibility to cooperate with those substrates in SSF system. Further experiment including initial profile production, effect of physical parameters (temperature, inoculum size and substrate quantity) and final profile production, were carried out. For initial profile, a basic condition of SSF which consisted 70% (v/w) of moisture content (adjusted to pH 6.0), 5 g substrates mixture (ungrounded size), 1x107 spore/ml of inoculum size and incubation temperature at 30±2 0C, was conducted in a flask system and fermented for 7 days. Those conditions allowed 160.03±3.79 mg lovastatin/g dry substrate of lovastatin production during initial stage. After a study of effect of physical parameters, it showed that the optimum temperature was still at ambient temperature (30±2 0C) and substrate quantity of 5 g but different inoculum size (1x105 spore/ml). Each parameters specifically temperature, inoculum size and substrate quantity produced 253.98±5.92 mg lovastatin/g dry substrate, 297.64±0.56 mg lovastatin/g dry substrate and 298.72±44.12 mg lovastatin/g dry substrate, respectively. Throughout the final profile, the production was 305.08±14.15 mg lovastatin/g dry substrate which made the total increment hit to almost 91%. In this experiment, lovastatin was subjected into high performance liquid chromatography (HPLC) with acetonitrile and phosphoric acid (pH 3.0) as a mobile phase.

A correlation between weedy species composition and 4 different planting practices in Peninsular Malaysia was being investigated from September 2011 – January 2012. Through this study, the noxious and competitive weed of rice were identified and counted, which should be helpful in developing a more sustainable weed control and management. This study was conducted at 24 different rice field covering four types of planting practices in Seberang Perai and MUDA area, namely wet seeding, water seeding, manual transplanting and mechanical transplanting method, using 0.5 x 0.5 m size quadrat with 20 samples for each field during rice at tillering to heading stage. A total of 27 weed species belonging to 14 families composing of 10 broadleaved, 8 grasses, 7 sedges and 2 submerged weed group were recorded. The dominance weeds species in four planting practices at both areas is Oryza sativa complex (weedy rice). Different dominance weed group observed in both areas due to different planting practices, such as in water seeding practice, broadleaved such Limnochoria flava and Monocharia vaginalis showed the highest I.V. for both areas, for wet seeding practice Echinochloa crus-galli and Leptochloa chinensis under grasses group have the highest I.V. and for manual and mechanical transplanting practice both have the same weed group which is Leptochloa chinensis.

This study aimed to investigate the antimicrobial activity of the endophytic fungus Phomopsis sp. ED2, which was previously isolated from the flower of the medicinal plant Orthosiphon stamineus Benth, in Penang, Malaysia. The 14 days-old fungal cultures were extracted with different organic solvents, include hexane, dichloromethane, ethyl acetate and butanol. The antimicrobial activities of the extracts were tested by disc diffusion assay. Based on the results, most antimicrobial compounds were present in the ethyl acetate fraction, and this extract could significantly inhibit the activity of bacteria, yeasts and fungi. The results also indicate that the antimicrobial compounds were mainly associated with the fungal biomass and all the Gram-positive test bacteria were inhibited by the ethyl acetate extract of the fungal biomass. Notably, methicillin-resistant Staphylococcus aereus exhibited a high sensitivity to the extract, with a low minimal inhibitory concentration and low minimal lethal concentration. The isolate also effectively inhibited the growth of the dermatophytes Microsporum gypseum and Trichophyton rubrum. Preliminary phytochemical screening also demonstrated that the extract contains phenols and steroids which possess antimicrobial activity. These results reveal that the endophytic fungus Phomopsis sp. is potential source of novel chemotherapeutic agents

Energy crisis involved the excessive consumption of fuels causing the increased in energy demands, oil price and depletion of fossil fuels. This has resulted in generation of high level of greenhouse gases emission. Therefore, in order to overcome these problems, alternative fuel has to be produced. This study was conducted to isolate potential fungal strains which can hydrolyze oil-palm residues as feedstock for bioethanol production. One hundred and sixty four fungal isolates were isolated from various sources and were screened for reducing sugars and protein production using submerged fermentation system. Out of these, 65 fungal strains were found capable to produce high specific activity relatively on oil-palm residues with the assay condition of temperature at 50oC for incubation time of 24 hours. Fungal isolate namely, Penicillium rolfsii was selected for subsequent study since it showed the highest capability to hydrolyze oil-palm residues comparing to other fungal strains based on time-course profile for 48 hours incubation time. Capability of Penicillium rolfsii on hydrolysis of oil-palm residues was evaluated by comparing to type strain of NBRC7735 and commercial enzymes (Celluclast 1.5L and Accellerase®1500). Conversion of these lignocellulosic oil-palm residues into fermentable sugars by enzymatic hydrolysis for bioethanol production has to be further investigated to move towards on alternative, renewable, sustainable, efficient and cost effective energy source

Lantadenes are the pentacyclic triterpenoids present in the leaves of the plant Lantana camara. Pentacyclic triterpenes are often studied as their biological properties are considerable and contributes to the development of modern therapeutic drugs. In recent years various natural product based compounds are extensively studied for various pharmacological activities including antioxidant activity. Therefore, this study aims to determine the in vitro antioxidant activity of Lantadene A (from Lantana camara ) as results will enhance the knowledge of the compound towards development of hepatoprotective agents. The antioxidant assays performed on the compound were the DPPH radical scavenging assay, nitric oxide assay, superoxide anions scavenging activity and iron chelating assay. Results showed promising antioxidant activities as the IC50 for Lantadene A in the above assays were 6.574 mg/ml, 0.098 mg/ml, 2.506 mg/ml and 0.001 mg/ml respectively as compared to the standards (BHT, ascorbic acid and EDTA) 0.027 mg/ml, 0.075 mg/ml, 1.025 mg/ml and 0.47 mg/ml respectively. The DPPH radical scavenging assay for Lantadene A was weaker than BHT while iron chelating assay of Lantadene A is much stronger than the standard. The rest of the assays were comparable to the reference standards. These results suggest that Lantadene A can be a potential cadidate to be developed as an antioxidant.

DNA barcoding has been accepted nowadays as a globally accessible tool to delimitate and identify new species, as it can provide accurate and automated species identification through the use of standard gene, Cytochrome oxidase I (COI). As a result, DNA barcoding has become a perfect molecular tool to identify fish products and detect wrongly labelled fish in the market as it can identify fish species even without the presenceof complete morphological characteristics. Here we collected samples from sushi restaurants to investigate and identify the precise species identity of raw fish sushi products because most of them were labelled with only common names such as Tuna, Salmon and Butterfish without providing the scientific name of the fishes. Species identities of seven specimens from two sushi restaurants were DNA barcoded utilising the cytochrome oxidase I (COI) gene. The data were BLAST with GenBank and BOLD to confirm species identification. The results showed 100% matches that there was nosubstitution and wrongly labelling of species as the Salmon sushi matched the database sequences of Salmo salar, Tuna to Thunnus albacares and Butterfish to Lepidocybium flavobrunneum. The investigation of these fishproduct true identities should be carried out routinely to ensure consumer protection from mislabelling and substitution for a cheaper fishin order to avoid health issuessuch as allergic reaction due to intake of the wronglylabelled product

A small infectious micro-organism that able to replicate only inside the living cells is named as viruses, which are also the most abundant life form on the earth. These subcellular organisms can be classified into four groups ; animal, plant, archaea and bacteria viruses. Among them, bacteria viruses or also known as bacteriophages have the highest numbers with the total estimation of 1031 . The fact is that, until today only ~ 6,000 types of phages have been discovered since 1959 (ICTV report, 2011). Therefore, there are lots of new phages waiting to be discovered. Partial genomic studies have been conducted on a potential new bacteriophage isolated from goat faeces. Thus, to fulfil the objective of this study genomic characterization was carried out to discover more genomic details in order to reveal the true identity of the newly isolated phage . As first part of the analysis, phage genome was extracted to identify the phage's genome type and to estimate the genome size. Along with that, the extracted genome was used to proceed with the genome profiling and also for partial genome sequencing analysis. Based on the genomic analysis, the results showed the isolated phage carries DNA as it genetic material with the size of genome around 30-40kbp. Besides that, this phage produced different genomic profile in comparison with other known phages such as Lambda, T4 and T7 phages when digest with the same restriction enzymes. Besides that, based on partial genome sequencing and results run against NCBI database, this newly isolated phage might be related with another newly isolated phage known as Sodalis phage SO-1. As far as the genomic data collected, an assumption can be made that this isolated phage could be a new addition to the list of viruses in International Committee on Taxonomy of Viruses (ICTV) database.

The objectives of this study were to determine the current bird species present in the study areas and to analyze variation of feeding guilds in different habitat types. Point count and mist-netting methods were used for bird census in SF and OP, while only point count method was used in PF. Feeding guilds were determined for each species recorded. A total of 183 species representing 49 families were recorded at all study sites. Secondary forest scored 106 species, followed by PF with 70 species and OP with 58 species. The highest abundance of bird families observed in SF was Pycnonotidae (26.65%), Hemiprocnidae (19.77%) and Muscicapidae (7.10%); in OP, Pycnonotidae (21.59%), Muscicapidae (19.12%) and Sturnidae (17.95%); in PF, Ardeidae (29.09%), Sturnidae (10.15%) and Hirundinidae (7.86%). Alternative hypothesis established that the abundance of species is different across habitat types, F(2,105) = 99.83, p < 0.05. Eight feeding guilds were identified in paddy field and seven in both secondary forest and oil palm plantation. If forests were converted to OP feeding guild could possibly change with a decreased in insectivore, insectivore-frugivore, insectivore-nectarivore and frugivore species; and increased in carnivore, grainivore and omnivore species. If forests were converted to PF feeding guild could possibly change with a decreased in insectivore, insectivore-frugivore and frugivore species; and increased in carnivore, insectivorenectarivore, insectivore-grainivore, grainivore and omnivore species. Comparison between SF and OP with Mann-Whitney U-test showed significant differences in six feeding guilds, including insectivore, insectivore-frugivore, insectivore-nectarivore, frugivore, grainivore and omnivore. Comparison between SF and PF showed significant differences in five feeding guilds, comprising of carnivore, insectivore-grainivore, frugivore, grainivore and omnivore. Comparison between OP and PF showed all feeding guilds to be significantly different

To obtain higher reducing sugar production via solid state fermentation (SSF), it is necessary to develop a stabile bioprocess system. In this study, optimized the physical parameter of SSF in a shallow aluminium tray (30 cm x 20 cm x 6 cm) was carried out in order to maximize reducing sugar production by A. niger USM AI1 using oil palm frond as a substrate. Production of reducing sugars before optimization in tray system was 185.00 ± 2.85 mg / g substrate with the fungal growth of 2.32 mg ± 0.06 glucosamine / g substrate. However, after optimization of physical parameter (amount of substrate, inoculum size, temperature and moisture content in substrate) the maximum reducing sugar yield was achieved 251.13 ± 1.95 mg / g substrate with the fungus growth of 3.21 ± 0.10 mg glucosamine / g on the 4 days of cultivation period. The results showed that the production of reducing sugar was increased by 35.7% compared to before optimization. Thus, optimized the physical parameter of solid state fermentation in a tray system has succeeded in increasing the production of reducing sugars. To meet the increasing demands of reducing sugar from biomass, it is necessary to obtain the optimum condition in SSF process

Urtica dioica (Stinging nettle) leaves have been used as a traditional medicine to treatrheumatoid arthritis, to alleviate rheumatic pain benign prostatic hyperplasia (BPH), diuretic and prevention of kidney stones by local people in Middle East region especially in Iran, Turkey and East Europe. Hence, this investigation evaluates the antidepressant effect of selected crude extracts in the forced swimming test (FST) and tail suspension test (TST), two models predictive of antidepressant activity. The acute treatment of mice with extracts by intra-peritoneal (i.p.) route significantly reduced the immobility time in the FST (50 and 100 mg/kg) and TST (50 and 100 mg/kg), as compared to positive controls (haloperidol and fluoxetine) at 1 and 10 mg/kg, respectively. On the third day of experiment, a significant decrease of mobility was observed for chloroform extract (CE I) and butanol extract (BE II) compared to first day. CE I and BE II led to reduction of immobility time, as the selected extracts with two doses administered were different compared to the control, in the FST method by 65.37% and53.92% for 100 mg/kg, respectively. However, CE I showed the best result compared to our positive controls. Similar results of increased antidepressant effect, that was, of immobility time depending on the concentration administered, were obtained with the TST method. Also our data showed that there was no significant differences between doses (50 and 100 mg/kg). The results suggested that the antidepressant action of the butanol extract and of U. dioica its fraction (BE II2) was mediated by an interaction with 5-hydroxytrptamine (5-HT). U. dioica showed a potential source for the isolation of important natural products with antidepressant-like properties. However, further studies are still required

The progressive depletion of fossil fuels has been causing increasing concern on rising energy consumption and environmental issues, such as greenhouse gas emission (GHG) and global warming. Due to low productivity of oil-palm tree after 20 - 25 years, the trees passed their economic age followed by the cutting-activity for replanting. Consequently, the old oil-palm trunks are one of the most abundantly available renewable resources produced, especially by Indonesia and Malaysia. We found that the felled oil palm trunk contains large quantity of sap with high concentration of free sugar contents. The oil-palm trunk residues which are the residual substances after squeezing sap will be discharged in large quantity. Composition analysis revealed that oil-palm residues mainly consisted of 73.12% holocellulose (cellulose and hemicellulose) and 24.6% of lignin. We tried the screening of filamentous fungus which can produce high-activity enzyme against oil-palm trunk residues as feedstock of bioethanol production. A filamentous fungus, which is Penicillium rolfsii with strong activity against oil-palm trunk residues was selected for saccharification experimental study. The result showed that higher amount of sugar production was achieved comparing to the commercial enzymes (Celluclast 1.5L and Accellerase®1500) on hydrolysis of oil palm residues, which is 1 to 2-fold of higher activity. Hence, Penicillium rolfsii have attracted a great deal of interest as oil-palm residues degrader due to their superiority activity against commercial enzymes.

One of the prerequisites for achieving autonomous flight, in machines as well as organisms, is the maintenance of a stable attitude relative to the vertical direction. In order to obtain attitude information, it is possible to use visual cues, such as the mean direction of illumination, the position of the horizon or optic flow. Recently, visual attitude stabilization has been implemented in a number of designs for micro-aerial vehicles. It is also being used by flying insects, and many of them carry ocelli, a supplementary set of simple lens eyes that appear to be specialized for attitude stabilization. These ocelli are particularly well developed in dragonflies, which are among the most competent fliers in existence. We have explored the dragonfly ocellar system, identifying the spatiotemporal transfer functions of its components, namely the dioptric system, the photoreceptor neurons, and, most importantly, the secondorder neurons which are the final stages in processing visual information. The outputs of a total of 15 neurons form a map of part of the visual world, covering a wide range (200 deg) of azimuth along the horizon. In elevation, the range is narrow (30 deg) and different elevations are not mapped onto different neurons, but the outputs of all neurons contain a component that is sensitive to optic flow in elevation. Thus, it appears that the dragonfly ocellar system uses an approach that distinguishes it from existing technical horizon detection algorithms. Our knowledge about details of the system is sufficient to implement it in hardware and to commence testing in realistic situations.

Urbanisation affects indigenous fauna in many ways; some species persist and even increase in urban areas, whereas others are lost. The causative mechanisms determining species persistence remain elusive; however an understanding of such mechanisms is crucial to conservation planning. In this thesis, I examined the urban landscape ecology of insectivorous bats in Sydney, Australia, across multiple ecological scales. I used a combination of mensurative and manipulative field examinations to address the mechanisms influencing bat distribution, community assembly and resource use. Firstly, using data collected from ultrasonic bat detectors at a landscape scale, I show that the degree of urbanisation, amount of bushland remaining, and landscape geology, influenced bat activity and structures the bat community into trait-specific groups. Open-adapted bats were associated with areas of greater housing density in more fertile areas, while clutter-adapted bats were associated with greater amounts of bushland occurring on less fertile geologies. I then explored patterns of insect biomass, revealing that landscape geology and habitat loss via urbanisation significantly alters prey biomass and the foraging patterns of bats. Species-specific habitat models were then developed, revealing substantial variation in the sensitivity of species to urbanisation, which was influenced by their biological traits. Using radio-telemetry in a suburban setting I examined fine-scale responses, showing that sensitivity to urbanisation substantially reduced the foraging and roosting range of a clutter-adapted species, Gould’s long-eared bat Nyctophilus gouldi which was restricted to larger remnant bushland (30 ha) for both roosting and foraging. Finally, I show experimentally that interspecific interactions at the scale of a tree hollow, including competition from hollow-using birds and predation by abundant urban mammals, have the potential to alter bat roosting behaviour, rendering hollow

Population structure, gene flow and dispersal are some of the most commonly estimated population parameters in population genetics, evolutionary biology and conservation genetics. The primary aim of thesis is to test the precision and accuracy of genetic estimates of population structure, gene flow and dispersal. The controlled replicated Drosophila melanogaster experiments of known effective population size (Ne = 14.3) and dispersal rate (m = 0.0025 - 0.04) all adhered to Wright’s demographic island model. Three statistical approaches were empirically tested: 1) the conversion of population structure to gene flow using FST, RST, SHUA and PhiST ; 2) the private alleles method to estimate gene flow; 3) a Bayesian assignment method to estimate dispersal (BAYESASS 1.2). Even in the best-case scenario, almost all current methods except SHUA significantly underestimate population structure, and consequently overestimate gene flow and dispersal when applied to real populations. It was crucial to ensure that the manipulated rate of gene flow was correctly defined. This led to three supporting investigations of hybrid performance, inversion polymorphisms and effective population size. The hybrid performance investigation demonstrated that the manipulated rate of gene flow had not been unexpectedly inflated by hybrid vigour or reduced by breakdown. These experiments also demonstrated that close inbreeding is not a necessary precondition for hybrid vigour or breakdown, which is important for conservation strategies involving induced dispersal. The investigation of inversion polymorphisms ensured that the manipulated rate of gene flow was not affected by selection on inverted regions. The effective population size investigation used a temporal estimation method to confirm that the Ne was accurately predicted by an N:Ne ratio of 0.286. Additionally this experiment showed that the single-sample estimation methods implemented by ONeSAMP or LDNE resulted in downwardly biased estim

UNIVERSITI SAINS MALAYSIA Second Semester Examination Academic Session 2008/2009 Aprii/Mei 2009 801 109/4- Biostatistics [Biostatistik] Duration: 3 hours [Masa : 3 jam]

Per-Arnt-Sim (PAS) domains play a critical role in signal transduction in multidomain proteins by sensing diverse environmental signals and regulating the activity of output domains. Multiple PAS domains are often found within a single protein. The NifL regulatory protein from Azotobacter vinelandii contains tandem PAS domains, the most N-terminal of which, PAS1, contains a FAD cofactor and is responsible for redox sensing, whereas the second PAS domain, PAS2, has no apparent cofactor and its function is unknown. Amino acid substitutions in PAS2 were identified that either lock NifL in a form that constitutively inhibits NifA or that fail to respond to the redox status, suggesting that PAS2 plays a pivotal role in transducing the redox signal from PAS1 to the C-terminal output domains. The isolated PAS2 domain is a homodimer in solution and the subunits are in rapid exchange. PAS2 dimerization is maintained in the redox signal transduction mutants, but is inhibited by substitutions in PAS2 that lock NifL in the inhibitory conformer. Our results support a model for signal transduction in NifL, whereby redox-dependent conformational changes in PAS1 are relayed to the C-terminal domains via changes in the quaternary structure of the PAS2 domain.

The University of Sydney eBot project was designed as a collaborative, sustainable repository for digital botanical objects. From its inception the repository was viewed as an effective way to bring together the collections of images and resources that we use in research and to support learning and teaching of undergraduate Plant Sciences at The University of Sydney.Objects contained within the repository range from the microscopic to entire landscapes. They include digitised herbarium specimens and associated temporal and spatial data. The metadata supporting the system enable effective archiving and retrieval of objects and is informed by international developments in botanical digital standards. The strength of this repository is that part of the metadata maps to the currently accepted taxonomy for the green plants. The eBot schema was derived from a range of descriptive standards, including the Herbarium Information Standards and Protocols for Interchange of Data (HISPID). This will ensure compatibility with digital herbaria in Australia. In addition to describing the scientific content of objects, the project addresses access and sustainability issues by including rights management data and information about the technical attributes of each object. To ensure the integrity of database content, all objects are validated by an expert reviewer prior to the images going ‘live’. eBot will be accessible later in 2008. Our view is that the project has potential to be used beyond the Plant Sciences and outside the university environment.

In order to identify stability constraints in flapping-winged MAVs, within the context of longitudinal stabilization of flight attitude, the question is examined whether insects are capable of controlling flight attitude at the temporal resolution of a single wing beat. It is found that the phenomenon of phase locking between a periodic light flash and the wingbeat of insects is suitable for the examination of the time resolution with which vision contributes to stabilization. In tethered locusts, flying in a wind tunnel with a wingbeat frequency of 22 Hz, phase locking can be readily obtained by a periodic stimulus of UV light. It is suggested that the effect is a by-product of the animal continuously trying to apply corrections. Therefore, in the closed-loop situation of free flight, frequency components of the visual input at or above wing beat rate are also present and must contribute to stability control. The response is mediated by the median ocellus. In dragonflies, with a wingbeat frequency of 50 Hz, the effect is not observed. This suggests that organisms or MAV of the size and wingbeat rate of locusts require active damping by visual inputs, whereas the same is not necessary in smaller systems., Prepared in cooperation with Philipps-Universitaet Marburg, Germany.

Tertiary Biology students are expected to calculate parameters from their experimental data gathered in practical classes, interpret the meaning(s) of these biological parameters and then discuss their findings in the context of the published literature. As teachers we expect students to have developed sound numeracy skills from their previous studies and be able to transfer these numeracy skills into their studies in Biology. However, Biology students are less than confident about performing calculations. Using research on student anxiety of learning mathematical skills (Meece , Wigfield and Eccles 1990; Boyd, Cullen, Bass, Pittman and Regan 1998; Klinger 2004) and self-efficacy intervention strategies (Hattie, Biggs and Purdie 1996; Pajares, Miller and Johnson 1999; Phan and Walker 2000; Schulz 2005), a numeric skills task was designed for second year plant science students and has been implemented since 2001. The numeric skills task allows each student to determine their confidence in: (a) their understanding of numeric concepts; (b) their understanding of quantities used in plant physiology; and, (c) their ability to calculate and convert between units of measure. An evaluation of the task shows that although all students were able to demonstrate their understanding of a physical parameter (e.g., volume), 32% of students were not confident with applying this understanding to estimating volumes, e.g., the volume of the tutorial room. A high proportion of students (47%) lacked confidence with converting between cubic metres and litres. Feedback from open-ended responses was categorised to measure student engagement with the task. Students who were the least confident with their answers had high levels of engagement with the numeracy task compared with those students who were more confident with their numeracy skills, indicating that students most likely to benefit from the task had been successfully targeted. Enabling students to engage in their own skills develop

Powdery mildew of rubber tree caused by Oidium heveae is an important disease of rubber plantations worldwide. Identification and classification of this fungus is still uncertain because there is no authoritative report of its morphology and no record of its teleomorphic stage. In this study, we compared five specimens of the rubber powdery mildew fungus collected in Malaysia, Thailand, and Brazil based on morphological and molecular characteristics. Morphological results showed that the fungus on rubber tree belongs to Oidium subgen. Pseudoidium. Nucleotide sequence analysis of the ribosomal DNA internal transcribed spacer (ITS) region and the large subunit rRNA gene (28S rDNA) were conducted to determine the relationships of the rubber powdery mildew fungus and to link this anamorphic fungus with its allied teleomorph. The results showed that the rDNA sequences of the two specimens from Malaysia were identical to a specimen from Thailand, whereas they differed by three bases from the two Brazilian isolates: one nucleotide position in the ITS2 and two positions in the 28S sequences. The ITS sequences ofthe two Brazilian isolates were identical to sequences of Erysiphe sp. on Quercus phillyraeoides collected in Japan, although the 28S sequences differed at one base from sequences of this fungus. Phylogenetic trees of both rDNA regions constructed by the distance and parsimony methods showed that the rubber powdery mildew fungus grouped with Erysiphe sp. on Q. phillyraeoides with 100% bootstrapsupport. Comparisons of the anamorph of two isolates of Erysiphe sp. from Q. phillyraeoides with the rubber mildew did not reveal any obvious differences between the two powdery mildew taxa, which suggests that O. heveae may be an anamorph of Erysiphe sp. on Q. phillyraeoides. Cross-inoculation tests are required to substantiate this conclusion.

To investigate the phylogenetic relationships among the powdery mildew fungi of some economically important tropical trees belonging to Oidium subgenus Pseudoidium, we conducted molecular phylogenetic analyses using 30 DNA sequences of the rDNA internal transcribed spacer (ITS) regions and 26 sequences of the domains D1 and D2 of the 28S rDNA obtained from the powdery mildews on Hevea brasiliensis (para rubber tree), Anacardium occidentale (cashew), Bixa orellana, Citrus spp., Mangifera indica (mango), and Acacia spp. The results indicate that the powdery mildew fungi isolated from these tropical trees are closely related to one another. These powdery mildews are also closely related to E. alphitoides (including Erysiphe sp. on Quercus phillyraeoides). Because of the obligate biotrophic nature of the powdery mildew fungi, the relationship between powdery mildews and their host plants is conservative. However, the present study suggests that a particular powdery mildew species has expanded its host ranges on a wide range of the tropical trees. This article also suggests that a powdery mildew fungus distributed in temperate regions of the Northern Hemisphere expanded its host ranges onto tropical plants and may be a good example of how geographical and host range expansion has occurred in the Erysiphales.

Filamentous fungi of the subphylum Pezizomycotina are well known as protein and secondary metabolite producers. Various industries take advantage of these capabilities. However, the molecular biology of yeasts, i.e. Saccharomycotina and especially that of Saccharomyces cerevisiae, the baker's yeast, is much better known. In an effort to explain fungal phenotypes through their genotypes we have compared protein coding gene contents of Pezizomycotina and Saccharomycotina. Only biomass degradation and secondary metabolism related protein families seem to have expanded recently in Pezizomycotina. Of the protein families clearly diverged between Pezizomycotina and Saccharomycotina, those related to mitochondrial functions emerge as the most prominent. However, the primary metabolism as described in S. cerevisiae is largely conserved in all fungi. Apart from the known secondary metabolism, Pezizomycotina have pathways that could link secondary metabolism to primary metabolism and a wealth of undescribed enzymes. Previous studies of individual Pezizomycotina genomes have shown that regardless of the difference in production efficiency and diversity of secreted proteins, the content of the known secretion machinery genes in Pezizomycotina and Saccharomycotina appears very similar. Genome wide analysis of gene products is therefore needed to better understand the efficient secretion of Pezizomycotina. We have developed methods applicable to transcriptome analysis of non-sequenced organisms. TRAC (Transcriptional profiling with the aid of affinity capture) has been previously developed at VTT for fast, focused transcription analysis. We introduce a version of TRAC that allows more powerful signal amplification and multiplexing. We also present computational optimisations of transcriptome analysis of non-sequenced organism and TRAC analysis in general. Trichoderma reesei is one of the most commonly used Pezizomycotina in the protein production industry. In order to understand, Monissa elintarvike-, kangas-, puunjalostus- ja energiateollisuuden prosesseissa tarvitaan entsyymejä. Näillä muunnellaan biomassan ominaisuuksia, esimerkiksi juoksutetaan juustoa, valkaistaan farkkuja tai paperia. Entsymaattinen käsittely on usein ympäristöystävällisempää kuin vastaava käsittely kemikaaleilla. Homesieniä käytetään entsyymien ja muiden proteiinien tuottamiseen. Proteiinit voivat olla peräisin myös muista eliöistä, esimerkiksi kasveista tai nisäkkäistä. Trichoderma reesei on trooppinen home, joka on tunnettu proteiinin tuottokyvystään ja sitä käytetään laajasti Suomessa ja muualla maailmassa. Tässä työssä on vertailtu home- ja hiivasienten perimiä laskennallisin metodein. Hiivoilla on puolet pienemmät perimät kuin homeilla ja ne tuottavat vähemmän proteiineja. Tehdyn vertailun perusteella ymmärrämme paremmin sieniperimien suhteita sienten havaittaviin ominaisuuksiin eli ilmiasuun. Onnistunut sienten perimän muuntelu niiden tuotto ominaisuuksien parantamiseksi edellyttää perimän ja ilmiasun suhteiden yksityiskohtaista ymmärtämistä. Perimässä oleva tieto muuttuu eliöiden ominaisuuksiksi monen välivaiheen kautta. Siksi pelkän perimän laskennallisen analyysin pohjalta on vaikea päätellä miten eliön perimää tulisi muunnella sen ominaisuuksien parantamiseksi. Perimä ilmentyy eri elinolosuhteissa eri tavoin ja ilmentymisen havainnoiminen on yksi tärkeimpiä tapoja tutkia eliön perimän ja ilmiasun suhdetta. Tässä työssä on kehitetty niin laskennallisia kuin laboratoriometodeja ilmentymisen tutkimiseen ja testattu niiden soveltuvuutta T. reesei:lle. Lisäksi T. reesei:n perimän ilmentymistä tutkittiin proteiinin tuoton kannalta kiinnostavissa olosuhteissa ja uusia perimän ilmentymisen muutoksia havaittiin. Ne saattavat osittain selittää homeiden erinomaista proteiinin tuottokykyä.

The blow fly, Lucilia sericata (Meigen) (Diptera: Calliphoridae), is found throughout Europe. In northern areas, in addition to breeding in carrion, it can also commonly act as primary facultative ectoparasite of sheep, resulting in animal suffering and production losses. However, in the south of Europe, L. Sericata is not usually implicated in myiasis and is found almost entirely in carrion. The causes of this behavioural difference are unclear. To begin to address the possible reasons for this difference, the present study examined the effects of competition on the survival and development of L. Sericata populations derived from southern Spain, England, and a hybrid derived from a cross between Spanish females and UK males. Larvae were reared at a range of different initial densities and the mortality, development rate, and size of the resultant adults were measured. Mortality increased significantly with density, but the Spanish population had a significantly higher mortality rate than the UK population at all densities. Similarly, adult size declined with increased larval density, but individuals from the Spanish population were consistently larger than those from the UK population at all densities. The mortality and size of the hybrids was consistently intermediate between the Spanish and UK populations. No consistent effects on development rate were observed. This study demonstrates that insects from northwestern and southern European population have qualitatively different life history traits and competitive abilities and may contribute towards explaining the different behaviour of populations of this species in different part of its distribution range.

Gametophytic self-incompatibility (SI) possessed by the Solanaceae is controlled by a highly polymorphic locus called the S locus. The S locus contains two linked genes, S-RNase, which determines female specificity, and the as yet unidentified pollen S gene, which determines male specificity in SI interactions. To identify the pollen S gene of Petunia inflata, we had previously used mRNA differential display and subtractive hybridization to identify 13 pollen-expressed genes that showed S -haplotype-specific RFLP. Here, we carried out recombination analysis of 1205 F 2 plants to determine the genetic distance between each of these S -linked genes and S-RNase . Recombination was observed between four of the genes (3.16, G211, G212, and G221) and S-RNase, whereas no recombination was observed for the other nine genes (3.2, 3.15, A113, A134, A181, A301, G261, X9, and X11). A genetic map of the S locus was constructed, with 3.16 and G221 delimiting the outer limits. None of the observed crossovers disrupted SI, suggesting that all the genes required for SI are contained in the chromosomal region defined by 3.16 and G221 . These results and our preliminary chromosome walking results suggest that the S locus is a huge multi-gene complex. Allelic sequence diversity of G221 and 3.16, as well as of 3.2, 3.15, A113, A134 and G261, was determined by comparing two or three alleles of their cDNA and/or genomic sequences. In contrast to S-RNase, all these genes showed very low degrees of allelic sequence diversity in the coding regions, introns, and flanking regions.

Arsenic resistance in the acidophilic iron-oxidizing archaeon " Ferroplasma acidarmanus " was investigated. F. acidarmanus is native to arsenic-rich environments, and culturing experiments confirm a high level of resistance to both arsenite and arsenate. Analyses of the complete genome revealed protein-encoding regions related to known arsenic-resistance genes. Genes encoding for ArsR (arsenite-sensitive regulator) and ArsB (arsenite-efflux pump) homologues were found located on a single operon. A gene encoding for an ArsA relative (anion-translocating ATPase) located apart from the arsRB operon was also identified. Arsenate-resistance genes encoding for proteins homologous to the arsenate reductase ArsC and the phosphate-specific transporter Pst were not found, indicating that additional unknown arsenic-resistance genes exist for arsenate tolerance. Phylogenetic analyses of ArsA-related proteins suggest separate evolutionary lines for these proteins and offer new insights into the formation of the arsA gene. The ArsB-homologous protein of F. acidarmanus had a high degree of similarity to known ArsB proteins. An evolutionary analysis of ArsB homologues across a number of species indicated a clear relationship in close agreement with 16S rRNA evolutionary lines. These results support a hypothesis of arsenic resistance developing early in the evolution of life.