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Molecular Biology Reports - Stripe rust and leaf rust are among the most devastating diseases of wheat, limiting its production globally. Wheat wild relatives harbour genetic diversity for new...  相似文献   
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A novel method based on (1) initial microbiological screening and (2) a highly specific PCR is described for selection of strains expressing YGNGV motif-containing pediocin. Initial screening is carried out using spot on the lawn assay for selection of acid-free, hydrogen peroxide (H2O2)-free and secreted heat-stable inhibitory activity producing strains. This is followed by highly specific PCR for amplification of 406-bp fragment using forward primer: 5′-tggccaatatcattggtggt-3′ targeting signal peptide sequence of pediocin structural gene and reverse primer: 5′-ctactaacgcttggctggca-3′ encoding N-terminus of immunity gene. The assay was validated with Pediococcus pentosaceus NCDC273 and Pediococcus acidilactici NCDC252 using (1) digestion of amplified 406-bp fragment with HindIII restriction enzyme-producing two restriction fragments of expected sizes (227 and 179 bp), (2) nucleotide sequencing of 406-bp fragment from both strains found these pediocins identical to pediocin PA-1/AcH and (3) identification of both pediocins as pediocin PA-1 at protein level using RP-HPLC. The assay was used for screening six strains (3 pediococci, 2 lactobacilli and an Enterococcus faecium) producing acid-free, hydrogen peroxide (H2O2)-free and secreted heat-stable inhibitory activity. This resulted in the detection of three new strains (P. pentosaceus NCDC35, E. faecium NCDC124 and Lactobacillus plantarum NCDC20) producing YGNGV motif-containing pediocins.  相似文献   
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The chlorophyte microalga Lobosphaera incisa was isolated from the snowy slopes of Mt. Tateyama in Japan. This microalga stores exceptionally high amounts of the omega-6 LC-PUFA arachidonic acid in triacylglycerols, and therefore represents a potent photosynthetic source for this essential LC-PUFA. Assuming that freezing tolerance may play a role in adaptation of L. incisa to specific ecological niches, we examined the capability of L. incisa to tolerate extreme sub-zero temperatures. We report here, that the vegetative cells of L. incisa survived freezing at −20°C and −80°C (over 1 month), without cryoprotective agents or prior treatments. Cells successfully recovered upon thawing and proliferated under optimal growth conditions (25°C). However, cells frozen at −80°C showed better recovery and lower cellular ROS generation upon thawing, compared to those preserved at −20°C. Photosynthetic yield of PSII, estimated by Fv/Fm, temporarily decreased at day 1 post freezing and resumed to the original level at day 3. Interestingly, the thawed algal cultures produced a higher level of chlorophylls, exceeding the control culture. The polar metabolome of the vegetative cells comprised a range of compatible solutes, dominated by glutamate, sucrose, and proline. We posit that the presence of endogenous cryoprotectants, a rigid multilayer cell wall, the high LC-PUFA content in membrane lipids, and putative cold-responsive proteins may contribute to the retention of functionality upon recovery from the frozen state, and therefore for the survival under cryospheric conditions. From the applied perspective, this beneficial property holds promise for the cryopreservation of starter cultures for research and commercial purposes.  相似文献   
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Objectives

To describe alcohol drinking patterns among participants in Katutura, Namibia, and to evaluate brief versions of the AUDIT against the full AUDIT to determine their effectiveness in detecting harmful drinking.

Methods

A cross-sectional survey was conducted in four constituencies and 639 participants, 18 years or older, completed a sociodemographic survey and the AUDIT. The effectiveness of the AUDIT-C (first three questions) and the AUDIT-3 (third question) was compared to the full AUDIT.

Results

Approximately 40% were identified as harmful, hazardous or likely dependent drinkers, with men having a higher likelihood than women (57.2% vs. 31.0%, p<.0001). Approximately 32% reported making and/or selling alcohol from home. The AUDIT-C performed best at a cutoff ≥ 3, better in men (sensitivity: 99.3%, specificity: 77.8%) than women (sensitivity: 91.7%, specificity: 77.4%). The AUDIT-3 performed poorly (maximum sensitivity: < 90%, maximum specificity: <51%). According to AUROC, the AUDIT-C performed better than the AUDIT-3.

Conclusions

A large proportion of participants met criteria for alcohol misuse, indicating a need for screening and referral for further evaluation and intervention. The AUDIT-C was almost as effective as the full AUDIT and may be easier to implement in clinical settings as a routine screening tool in resource-limited settings because of its brevity.  相似文献   
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A series of 3-substituted 1,4-benzodiazepin-2-ones derived from S and R amino acids were evaluated for their anti-ischemic activity in vitro. Treatment with compounds 7h, 16, 9d, and 17 decreased the apoptotic neuronal number, however increased the neuronal viability. The compounds decreasing apoptosis could protect neurons from the ischemic injury. The difference in the activities of 1,4-benzodiazepin-2-ones derived from S- and R-amino acids is discussed and explained on the basis of molecular modeling studies.  相似文献   
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The extracellular enzyme alginate lyase produced from marine fungus Aspergillus oryzae isolated from brown alga Dictyota dichotoma was purified, partially characterized, and evaluated for its sodium alginate depolymerization abilities. The enzyme characterization studies have revealed that alginate lyase consisted of two polypeptides with about 45 and 50 kDa each on 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis and showed 140-fold higher activity than crude enzyme under optimized pH (6.5) and temperature (35°C) conditions. Zn2+, Mn2+, Cu2+, Mg2+, Co2+ and NaCl were found to enhance the enzyme activity while (Ca2+, Cd2+, Fe2+, Hg2+, Sr2+, Ni2+), glutathione, and metal chelators (ethylenediaminetetraacetic acid and ethylene glycol tetraacetic acid) suppressed the activity. Fourier transform infrared and thin-layer chromatography analysis of depolymerized sodium alginate indicated the enzyme specificity for cleaving at the β-1,4 glycosidic bond between polyM and polyG blocks of sodium alginate and therefore resulted in estimation of relatively higher polyM content than polyG. Comparison of chemical shifts in 13C nuclear magnetic resonance spectra of both polyM and polyG from that of sodium alginate also showed further evidence for enzymatic depolymerization of sodium alginate.  相似文献   
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Search for new antimicrobial agents led to the synthesis of series of N-1, C-3 and C-5 substituted bis-indoles. Their evaluation for antifungal and antibacterial activities resulted in the optimization of pyrrolidine/morpholine/N-benzyl moiety at the C-3 end and propane/butane/xylidine groups as linkers between two indoles for significant inhibition of microbial growth. Preliminary investigations have identified three highly potent antimicrobial agents. Dockings of these molecules in the active sites of lanosterol demethylase, dihydrofolate reductase and topoisomerase II indicate their strong interactions with these enzymes.  相似文献   
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