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Bdellovibrio, δ-proteobacteria, including B. bacteriovorus (Bba) and B. exovorus (Bex), are obligate predators of other Gram-negative bacteria. While Bba grows in the periplasm of the prey cell, Bex grows externally. We have analyzed and compared the transport proteins of these 2 organisms based on the current contents of the Transporter Classification Database (TCDB; www.tcdb.org). Bba has 103 transporters more than Bex, 50% more secondary carriers, and 3 times as many MFS carriers. Bba has far more metabolite transporters than Bex as expected from its larger genome, but there are 2 times more carbohydrate uptake and drug efflux systems, and 3 times more lipid transporters. Bba also has polyamine and carboxylate transporters lacking in Bex. Bba has more than twice as many members of the Mot-Exb family of energizers, but both may have energizers for gliding motility. They use entirely different types of systems for iron acquisition. Both contain unexpectedly large numbers of pseudogenes and incomplete systems, suggesting that they are undergoing genome size reduction. Interestingly, all 5 outer-membrane receptors in Bba are lacking in Bex. The 2 organisms have similar numbers and types of peptide and amino acid uptake systems as well as protein and carbohydrate secretion systems. The differences observed correlate with and may account, in part, for the different lifestyles of these 2 bacterial predators.

Background and Objectives: Probiotics are added into the food or feed systems and provide beneficial effects to the human or animal health. This study aimed to isolate the gastrointestinal native Lactobacillus strains with high probiotic, cholesterol-assimilation and aflatoxin-degradation capabilities from native chickens. Materials and Methods: About 70 Lactobacillus isolates were isolated from ileum of the Fars province native chickens and were investigated for their probiotic properties. Results: Of 70 Lactobacillus isolates, 10 showed high probiotic capabilities, including survival at acidic conditions (pH up to 2.5), tolerance of 0.5% bile and 6-10% NaCl salts, growth in a wide range of temperature from 15 to 45°C, antagonistic effects against different important bacterial pathogens (Pseudomonas aeruginosa, Escherichia coli, Streptococcus mutans, Clostridium defficile, Enterococcus hirae, Salmonella enterica and Staphylococcus aureus) and sensitivity to some important antibiotics. The selected strains had an aggregation time less than 120 min. The 16S-rDNA sequencing showed that the selected strains were highly related to Lactobacillus reuteri and L. casei. Finally, the selected strains in this study along with 10 other probiotic strains isolated and characterized in our pervious study were used to evaluate their cholesterol assimilation and aflatoxin B1 degradation capabilities. The potentials of cholesterol assimilation of the selected strains were significantly different (P<0.05) and ranged from 2.3% to 99%. The highest content of cholesterol assimilation was obtained in isolates M20 and M4 with more than 98% absorption. Moreover, four strains 43, OR7, M21 and OR9 were able to absorb AFB1 with 58.6%, 52.33%, 47% and 31.6% efficiency respectively. Conclusion: It could be concluded that the strains 43, M21 and OR7 showed high probiotic potentials for application in the poultry industry. [ABSTRACT FROM AUTHOR]

Context The new “omics” studies on the genus Quercus are of importance to help finding efficient strategies for overcoming environmental challenges, and to do this, presence of efficient DNA extraction protocols for different Quercus species are very critical. Aims The objective of the present study was to develop new efficient methods for extraction of metagenomic DNA (mDNA) from of Persian oak (Quercus brantii Lindl.) tissues. Methods The efficiency of two newly developed mDNA extraction methods, including indirect SDS-based (ISB or concentrate method) and one spin column-based method (SCB) were compared to that of two classical direct methods, including CTABbased and SDS-based methods, and two commercial mDNA extraction kits. Results The maximum average yield of mDNA for all samples (leaf, stem, root, bulk, and rhizospheric soils) was obtained by SCB (258 ng/μl) and ISB (189 ng/μl) methods, respectively. Successful PCR amplification for 16SrRNA and ITS sequence was consistently observed for ISB, SCB, and kit-extracted mDNAs, which confirmed the high purity of mDNA extracted by these methods. The new methods showed more than 96% quantitative PCR efficiency, and partial restriction digestion and metagenomic library construction confirmed the high efficiency of the newly developed methods. Conclusion It could be concluded that two new protocols enhanced efficiency (yield, purity, and cost) of mDNA extraction from different tissues of Persian oak. [ABSTRACT FROM AUTHOR]

The objective of the current study was to evaluate the impact of wheat resistance on digestibility of Schizaphi.s graminum (Rondani) in the Cocciriella septempunctata L. gut. Four wheat genotypes including an ancient wheat species (Einkorn) and three Iranian wheat genotypes (Azadi, Ommid, and Moghan2) were used. Einkom was found to be a highly resistant species, while Azadi, Ommid, and Moghan2 were characterized as resistant, semiresistant, and susceptible genotypes, respectively, based on some biological parameters of S. graminum on these plants. Adult C. septempunctata starved for 24 h were fed one S. graminum reared on the selected wheat genotypes. A semiquantitative polymerase chain reaction technique using specific primers for the gene cytochrome oxidase II (COII) of S. graminum showed a significant effect of plant resistance on S. graminum DNA disappearance time. The DNA half-lives of S. graminum fed on Einkorn, Azadi, Ommid, and Moghan2 in C. septempunctata gut was 3.3,3.6,4.8, and 6.7 h, respectively. The findings suggest that digestibility of S. graminum fed on resistant plant genotypes is higher than those fed on susceptible plants because of the lighter weights and smaller sizes of the first. This phenomenon could result in faster ingestion of S. graminuni by C. septempunctata on these resistant plants. It is also possible that some metabolites found differentially in Einkorn and Azadi genotypes may have affected S. graminum quality as a food for C. septempunctata. [ABSTRACT FROM AUTHOR]

Biological parameters of Schizaphis graminum (Rondani) reared on an ancient wheat species (Einkorn) from England and five Iranian wheat genotypes (Azadi, Ommid, Marvdasht, Pishtaz and Moghan 2) were studied under controlled conditions at 22 ± 1°C, 65 ± 5% RH, 16:8 (L:D) h. The lowest rm value (0.261± 0.002 females/female/day) and net reproductive rate (R0) (28.747± 0.369) were recorded on Einkorn. The highest and the lowest finite rates of increase (λ) were on Moghan 2 and Einkorn, respectively. Also, the longest mean generation time (T) and doubling time (DT) with the lowest percentages of nymphal survival (79.5%) and fecundity over developmental time (35.739± 0.378 nymphs/female/day) were obtained on Einkorn. Adult longevity varied from 10.72± 0.123 days on Einkorn to 18.04± 0.212 days on Moghan 2. Therefore, our results showed that Einkorn, exerting a high level of antibiosis compared to other tested genotypes, may decrease the population density of the greenbug. [ABSTRACT FROM AUTHOR]

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One hundred and twenty-eight Bacillus thuringiensis isolates from fields of different ecological regions of Iran were collected to study the distribution and diversity of Dipteran-specific cry and cyt genes. The percentage of samples with Bt showed significant differences between different regions and also between different fields. The most Bt frequency was observed in the soil samples collected from Caspianic zone (7%) and soils of cotton (17%). Characterization of isolates was based on morphological characteristics of crystals, plasmid profiles and protein band patterns as well as PCR analysis using general and specific primers for 22 different cry and cyt genes encoding proteins active against mosquitoes. Thirty-eight different cry gene profiles were detected in this collection. Several of them were found to be different from all previously published profiles and none of the previous researches reported these numbers of profiles. Strains containing cry2-type genes were the most abundant and represent 57.1% of the isolates. Strains harboring cry24 and cry10 genes were also highly abundant (38.7 and 32.8%, respectively). cry11, cry4, cry17, cry19, cry21, cry29, cyt1, and cry9 genes were less abundant, found in 25.7, 14.3, 11.4, 1.4, 4.3, 1.4, and 10% of the strains, respectively. Among the cry2 gene containing isolates, 37.5% strains harbored cry2Aa, 55% cry2Ab, 2.5% cry2Ac, and 5% other or novel cry2-type genes . Among the cry4 gene containing isolates, 0% strains harbored cry4A, 60% cry4B, and 40% cry4C, cry4D or novel cry4 type genes. Finally, based on crystal morphology, protein patterns and PCR, 21 strains were selected as potentially high Dipteran-active for bioassays. Also our results showed that some of the isolates may harbor minimum a putative novel cry gene. [ABSTRACT FROM AUTHOR]

Recently, application of ionic liquids (ILs) has received much attention due to their special solvency properties as a promising method of pretreatment for lignocellulosic biomass. Easy recovery of ionic liquids, chemical stability, temperature stability, nonflammability, low vapor pressure, and wide liquidus range are among those unique properties. These solvents are also known as green solvents due to their low vapor pressure. The present study was set to compare the effect of five different ILs, namely, 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), 1-ethyl-3-methyl imidazolium diethyl phosphate ([EMIM][DEP]), 1-allyl-3-methylimidazolium chloride ([AMIM][Cl]), and 1-ethyl-3-methylimidazolium-hydrogen sulfate ([EMIM][HSO₄]), on corn stover in a bioethanol production process. The performance of ILs was evaluated based on the change observed in chemical structure, crystallinity index, cellulose digestibility, and glucose release. Overall, [EMIM][Ac]-pretreated corn stover led to significantly higher saccharification, with cellulose digestibility reaching 69% after 72 hr, whereas digestibility of untreated barley straw was measured at only 21%.