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The tryptophan is a precursor of the lipopeptide calcium dependent antibiotic (CDA), produced from Streptomyces coelicolor and closely related to important antibiotics such as daptomycin. We have focused our attention on the correlation between CDA production and tryptophan metabolism in order to identify new strategies aimed at increasing the production of peptide antibiotics.

Nella primavera 2008 nella città di Palermo, pupe, larve e di Punteruolo rosso sono stati prelevati da palme infestate ed e’ stato avviato lo studio della naturale incidenza di patogeni del punteruolo rosso. Specie fungine sono state isolate principalmente dalle pupe, infatti circa il 30% di queste erano colonizzate da funghi. I sintomi dell’infezione includevano rapida atrofia dei tessuti pupali, mancata fuoriuscita dell’adulto e morte. La dissezione delle pupe infette ha rivelato la crescita di un denso micelio, suggerendo la penetrazione delle ife e la patogenicita’. I putativi patogeni sono stati isolati su piastra e la loro identificazione e’ stata condotta mediante amplificazione e sequenziamento, di specifiche regioni del DNA genomico (marker molecolare ITS). Due dei quattro prodotti delle reazioni di amplificazione sono stati sequenziati ed è stata condotta l’analisi delle omologie di sequenza. I risultati hanno rivelato un elevato grado di omologia con le sequenze ITS di Trichosporon sp e di Pichia jadinii. Inoltre e’ stata condotta un’analisi mediante microscopia elettronica a scansione SEM

A juvenile specimen of the Green Turtle, Chelonia mydas, was recovered in Sicilian coastal waters close to Avola (Syracuse province, south-eastern Sicily, Italy). Before being released, the specimen was measured and inspected for the presence of ingested hooks or other possible harms to its health. A fragment of the mtDNA marker COI was amplified and sequenced in order to provide the first molecular data for the species from the central Mediterranean area. The possible influence of climate change on the occurrence of this thermophilic species in the central Mediterranean area is briefly discussed.

Background: The aim of this study was to analyse the nutraceutical properties of table green olives Nocellara del Belice, a traditional Mediterranean food. The Mediterranean Diet has as key elements olives and extra virgin olive oil, common to all Mediterranean countries. Olive oil is the main source of fat and can modulate oxidative stress and inflammation, whereas little is known about the role of olives. Moreover, emerging evidences underline the association between gut microbiota and food as the basis of many phenomena that affect health and delay or avoid the onset of some age-related chronic diseases. Methods: In order to show if table green olives have nutraceutical properties and/or probiotic effect, we performed a nutritional intervention, administering to 25 healthy subjects (mean age 38,3), 12 table green olives/day for 30 days. We carried out anthropometric, biochemical, oxidative stress and cytokines analyses at the beginning of the study and at the end. Moreover, we also collected fecal samples to investigate about the possible variation of concentration of Lactobacilli, after the olives consumption. Result: Our results showed a significant variation of one molecule related to oxidative stress, malondialdehyde, confirming that Nocellara del Belice green olives could have an anti-oxidant effect. In addition, the level of interleukin-6 decreased significantly, demonstrating how this food could be able to modulate the inflammatory response. Moreover, it is noteworthy the reduction of fat mass with an increase of muscle mass, suggesting a possible effect on long time assumption of table olives on body mass variation. No statistically significant differences were observed in the amount of Lactobacilli, although a trend towards an increased concentration of them at the end of the intervention could be related to the nutraceutical effects of olives. Conclusion: These preliminary results suggest a possible nutraceutical effect of daily consumption of green table olives Nocellara del Belice. To best of our knowledge, this is the first study performed to assess nutraceutical properties of this food. Of course, it is necessary to verify the data in a larger sample of individuals to confirm their role as nutraceuticals.

Human astroviruses (HAstVs) are important enteric pathogens that are genetically and antigenically heterogeneous and can be classified into eight sero/genotypes (HAstV-1 to -8) and different lineages within each HAstV type. This study describes the genetic diversity of HAstVs circulating in southern Italy over 14 years. Molecular analysis of HAstV-1 strains showed that three different lineages (1a, 1b and 1d) of the predominant genotype were circulating during the study period. The study of an archival collection of HAstV strains offers a unique opportunity to evaluate the patterns of variation of HAstV infections over the years and to correlate the observed epidemiological changes to the genetic variability of HAstVs.

HspR (heat shock protein regulator) acts as a negative regulator of different genes in many bacteria. In Streptomyces coelicolor hspR gene is part and the transcriptional repressor of the dnaK operon which encodes the DnaK, GrpE, DnaJ chaperone machines and HspR itself. Our experiments led us to the discovery of a second promoter, internal to dnaK operon, located upstream hspR gene. Transcription from this promoter was detected at 30 degrees C indicating that hspR could play a key physiological role.

Most enzymes involved in tryptophan catabolism via kynurenine formation are highly conserved in Prokaryotes and Eukaryotes. In humans, alterations of this pathway have been related to different pathologies mainly involving the central nervous system. In Bacteria, tryptophan and some of its derivates are important antibiotic precursors. Tryptophan degradation via kynurenine formation involves two different pathways: the eukaryotic kynurenine pathway, also recently found in some bacteria, and the tryptophan-to-anthranilate pathway, which is widespread in microorganisms. The latter produces anthranilate using three enzymes also involved in the kynurenine pathway: tryptophan 2,3-dioxygenase (TDO), kynureninase (KYN), and kynurenine formamidase (KFA). In Streptomyces coelicolor, where it had not been demonstrated which genes code for these enzymes, tryptophan seems to be important for the calcium- dependent antibiotic (CDA) production. In this study, we describe three adjacent genes of S. coelicolor (SCO3644, SCO3645, and SCO3646), demonstrating their involvement in the tryptophan-to-anthranilate pathway: SCO3644 codes for a KFA, SCO3645 for a KYN and SCO3646 for a TDO. Therefore, these genes can be considered as homologous respectively to kynB, kynU, and kynA of other microorganisms and belong to a constitutive catabolic pathway in S. coelicolor, which expression increases during the stationary phase of a culture grown in the presence of tryptophan. Moreover, the S. coelicolor ΔkynU strain, in which SCO3645 gene is deleted, produces higher amounts of CDA compared to the wild-type strain. Overall, these results describe a pathway, which is used by S. coelicolor to catabolize tryptophan and that could be inactivated to increase antibiotic production.

Both industry and academia have shown a growing interest in materials with antimicrobial properties suitable for food packaging applications. In this study, we prepared and characterized thin films of ethylene-co-vinyl acetate (EVA) copolymer with antimicrobial properties. The films were prepared with a film blowing process by incorporating a nisin preparation as an antimicrobial agent in the melt. Two grades of EVA containing 14 and 28% (wt/wt) vinyl acetate (EVA 14 and EVA 28, respectively) and two commercial formulations of nisin with different nominal activities were used. The effect of the nisin concentration also was evaluated. The films with the highest antimicrobial activity were those formulated with nisin at the highest activity and EVA with the highest content of vinyl acetate. The use of the commercial formulation of nisin with high activity in the EVA films allowed reduction in the amount of nisin needed to provide antimicrobial properties. Consequently, the mechanical properties of these films were only slightly inferior to those of the pure polymers. In contrast, films prepared by incorporating more of the nisin with lower activity had poor mechanical properties. The effect of different processing temperatures used in the preparation of the films on the antimicrobial properties of the films also was evaluated. The materials displayed antimicrobial properties even when they were prepared at temperatures as high as 160 °C, probably because of the very short processing time (60 to 90 s) required for preparation.

Northern blot hybridization is a useful tool for analyzing transcript patterns. To get a picture of what really occurs in vivo, it is necessary to use a protocol allowing full protection of the RNA integrity and recovery and unbiased transfer of the entire transcripts population. Many protocols suffer from severe limitations including only partial protection of the RNA integrity and/or loss of small sized molecules. Moreover, some of them do not allow an efficient and even transfer in the entire sizes range. These difficulties become more prominent in streptomycetes, where an initial quick lysis step is difficult to obtain. We present here an optimized northern hybridization protocol to purify, fractionate, blot, and hybridize Streptomyces RNA. It is based on grinding by a high-performance laboratory ball mill, followed by prompt lysis with acid phenol-guanidinium, alkaline transfer, and hybridization to riboprobes. Use of this protocol resulted in sharp and intense hybridization signals relative to long mRNAs previously difficult to detect.

The aim of the present work was the identification of the gene encoding for β-glucosidase and its partial sequencing in the strainsPichia anomala AL112,Hanseniaspora uvarum Y8 andSaccharomyces cerevisiae AL41. To this aim degenerated primers, designed on the basis of aminoacid similarities of four known yeast β-glucosidases, have been used in PCR amplifications. An expected fragment of about 200 bp was amplified from all the DNAs, cloned and sequenced. Sequence homology demonstrated for the first time the presence of a β-glucosidase encoding gene inHanseniaspora uvarum andSaccharomyces cerevisiae.

Through the screening of a Streptomyces coelicolor genomic library, carried out in a histidinol phosphate phosphatase (HolPase) deficient strain, SCO5208 was identified as the last unknown gene involved in histidine biosynthesis. SCO5208 is a phosphatase, and it can restore the growth in minimal medium in this HolPase deficient strain when cloned in a high or low copy number vector. Moreover, it shares sequence homology with other HolPases recently identified in Actinobacteria. During this work a second phosphatase, SCO2771, sharing no homologies with SCO5208 and all so far described phosphatases was identified. It can complement HolPase activity mutation only at high copy number. Sequence analysis of SCO5208 and SCO2771, amplified from the HolPase mutant strain, revealed that SCO5208 shows a mutation in a conserved amino acid, whereas SCO2771 does not show any mutation. All these results show that S. coelicolor SCO5208, recently renamed hisN, is the HolPase involved in histidine biosynthesis.

Biodeterioration of organic substrates is a process involving several types of micro/organisms and represents a ravelled problem particularly for confined environments (archives, libraries, hypogeal, museum), where microbial growth depends on a combination of factors such as relative humidity, indoor temperature fluctuation, water activity, chemical and physical properties of materials surface (Else et al., 2003; Gallo et al., 1999; Valentin, 2003). Both water condensation phenomena and poor ventilation, that allow micro-climate formation suitable for the development of microorganisms for fungi and bacteria that may release toxins with human health damaging proprieties, that may persist in the environment (Singh et al., 1995; Peltola et al., 2001). Studies on microbial communities structure in indoor environment reported an high contamination of bacteria such as Bacillus, Micrococcus, Streptomyces, Actinomycetes, among fungi as Penicillum, Cladosporium, Aspergillus, Alternaria, Trichoderma, Rhizopus, (Valentin, 2003). It is well known that ribosomal RNA genes are essential for all organisms, representing ideal loci for microbial characterization, for phylogenic study and for strains differentiation even within species (Cardinale et al., 2004; Gonzales, 2003). In this study we report a new sampling method and microbial identification strategies, based on PCR and microarray analysis, that can identify bacterial and fungal as biodeteriogens for works of art and/or pathogens for human, focalising our attention on microbial populations, present in the bioaerosol and on works of art surface.

We report the presence of bacterial colonization in library environment and on the books housed, performing morphological and bacterial molecular analyses. Isolated bacterial colonies were characterised by 16S rRNA locus and ITS (16S-23S rRNA Intergenic Transcribed Spacer) amplification and sequencing. The results of SEM observation and molecular analysis showed the prevalent presence of bacteria belonging to the family Micrococcaceae. We distinguished Kocuria rosea, Arthrobacter nicotianae, Micrococcus luteus and Curtobacterium flaccumfaciens which shows high cellulolytic activity.

Aims: Characterization of SCP2165, a plasmid identified in the Gram-positive bacterium Streptomyces coelicolor A3(2). Methods and Results: Pulsed-field gel electrophoresis (PFGE) of mycelia of a S. coelicolor strain embedded in low melting agarose revealed the presence of a plasmid. Restriction enzyme mapping and sequence analysis of a 2·1 kb fragment revealed that this plasmid could be SCP2. SCP2 and its spontaneous derivative SCP2* are self-transmissible plasmids and have chromosome mobilizing ability (c.m.a.). SCP2* has a c. 1000-fold increased c.m.a. compared with SCP2. Interestingly the plasmid, named SCP2165, shows a c.m.a. from 5 × 10−2 to 1 × 10−1 which is 50–100-fold higher than that described for crosses involving SCP2*. Conclusions: SCP2165 is a SCP2 derivative plasmid with the highest c.m.a. so far described for SCP2 derivative plasmids. PFGE, under conditions we used, seems to be a fast way to identify large circular plasmids in Streptomyces strains. Significance and Impact of the Study: Further knowledge of the SCP2 family may allow the construction of improved SCP2-derived cloning vectors. SCP2165 could be a potential tool for conjugational transfer of gene clusters between different Streptomyces species.