journal
MENU ▼
Read by QxMD icon Read
search

Applied and Environmental Microbiology

journal
https://www.readbyqxmd.com/read/29776932/-cg-med3-affects-cell-size-and-budding-index-to-coordinate-candida-glabrata-cell-growth
#1
Hui Liu, Lulin Kong, Yanli Qi, Xiulai Chen, Liming Liu
Candida glabrata is a promising microorganism for the production of organic acids. Here, we report deletion and quantitative expression approaches to elucidate the role of Cg Med3AB, a subunit of the mediator transcriptional co-activator, in regulating cell growth. Deletion of Cg Med3AB caused an 8.6% decrease in final biomass based on growth curve plots and 10.5% lower cell viability. Based on transcriptomics data, the reason for this growth defect was attributable to changes in expression of genes involved in pyruvate and acetyl-CoA-related metabolism in the Cgmed3abΔ strain...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776931/shuffling-the-neutral-drift-of-unspecific-peroxygenase-in-saccharomyces-cerevisiae
#2
Javier Martin-Diaz, Carmen Paret, Eva García-Ruiz, Patricia Molina-Espeja, Miguel Alcalde
Unspecific peroxygenase (UPO) is a highly promiscuous biocatalyst and its selective mono(per)oxygenase activity makes it useful for many synthetic chemistry applications. Among the broad repertory of library creation methods for directed enzyme evolution, genetic drift allows neutral mutations to be accumulated gradually within a polymorphic network of variants. In this study, we conducted a campaign of genetic drift with UPO in Saccharomyces cerevisiae so that neutral mutations were simply added and recombined in vivo With low mutational loading and an activity threshold of 45% of the parent's native function, mutant libraries enriched in folded and active UPO variants were generated...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776930/modifying-the-lantibiotic-mutacin-1140-for-increased-yield-activity-and-stability
#3
Mengxin Geng, Leif Smith
Mutacin 1140 belongs to the epidermin family of type AI lantibiotics. This family has a broad spectrum of activity against Gram-positive bacteria. The binding of mutacin 1140 to lipid II leads to the inhibition of cell wall synthesis. Pharmacokinetic experiments on type AI lantibiotics are generally discouraging for clinical applications due to their short half-life. The unprotected dehydrated and protease susceptible residues outside of the lanthionine rings may play a role in their short half-life in physiological settings...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776929/antibacterial-effects-of-phage-lysin-lysgh15-on-planktonic-cells-and-biofilms-of-diverse-staphylococci
#4
Yufeng Zhang, Mengjun Cheng, Hao Zhang, Jiaxin Dai, Zhimin Guo, Xinwei Li, Yalu Ji, Ruopeng Cai, Hengyu Xi, Xinwu Wang, Yibing Xue, Changjiang Sun, Xin Feng, Liancheng Lei, Wenyu Han, Jingmin Gu
Treatment of infections caused by staphylococci has become more difficult because of the emergence of multidrug-resistant strains as well as biofilm formation. In this study, we observed the ability of the phage lysin LysGH15 to eliminate staphylococcal planktonic cells and biofilms formed by Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus hominis All these strains were sensitive to LysGH15, showing reductions in bacterial counts of approximately 4 log units within 30 min after treatment with 20 μg/mL LysGH15, and the minimum inhibitory concentrations (MICs) ranged from 8 μg/mL to 32 μg/mL...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776928/enrichment-of-clinically-relevant-organisms-in-spontaneous-preterm-delivered-placenta-and-reagent-contamination-across-all-clinical-groups-in-a-large-uk-pregnancy-cohort
#5
Lydia J Leon, Ronan Doyle, Ernest Diez-Benavente, Taane G Clark, Nigel Klein, Philip Stanier, Gudrun E Moore
In this study differences in the placental microbiota of term and preterm deliveries from a large UK pregnancy cohort were studied using 16S targeted amplicon sequencing. The impact of contamination from DNA extraction, PCR reagents, as well as those from delivery itself were also examined. A total of 400 placental samples from 256 singleton pregnancies were analysed and differences investigated between spontaneous preterm, non-spontaneous preterm, and term delivered placenta. DNA from recently delivered placenta was extracted, and screening for bacterial DNA was carried out using targeted sequencing of the 16S rRNA gene on the Illumina MiSeq platform...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776927/ecological-engineering-helps-maximize-function-in-algal-oil-production
#6
Sara L Jackrel, Anita Narwani, Bastian Bentlage, Robert B Levine, David C Hietala, Phillip E Savage, Todd H Oakley, Vincent J Denef, Bradley J Cardinale
Algal biofuels have the potential to curb emissions of greenhouse gases from fossil fuels, but current growing methods fail to produce fuels that meet the multiple standards necessary for economical industrial use. For example, algae grown as monocultures for biofuel production have not simultaneously and economically achieved high yields of the high-quality, lipid-rich biomass desired for the industrial-scale production of bio-oil. Decades of study in the field of ecology have demonstrated that simultaneous increases in multiple functions, such as the quantity and quality of biomass, can occur in natural ecosystems by increasing biological diversity...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776926/occurrence-of-traditional-and-alternative-fecal-indicators-in-tropical-urban-environments-under-different-land-use-patterns
#7
Nazanin Saeidi, Xiaoqiong Gu, Tran Ngoc Han, Shin Giek Goh, Masaaki Kitajima, Ariel Kushmaro, Bradley William Schmitz, Karina Yew-Hoong Gin
This study evaluates the geospatial distribution of fecal indicator bacteria (FIB) (i.e., E. coli , Enterococcus spp.) and the alternative fecal indicator, pepper mild mottle virus (PMMoV), in tropical freshwater environments under different land use patterns. Results show that the occurrence and concentration of microbial fecal indicators was higher for urban-dominated areas than parkland-dominated, consistent with land use weightage. Significant positive correlations with traditional FIB indicate that PMMoV is a suitable indicator of fecal contamination in tropical catchments waters (0...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776925/unravelling-the-reduction-pathway-as-alternative-metabolic-route-to-hydroxycinnamate-decarboxylation-in-lactobacillus-plantarum
#8
Laura Santamaría, Inés Reverón, Félix López de Felipe, Blanca de Las Rivas, Rosario Muñoz
Lactobacillus plantarum is the lactic acid bacterial species most frequently found in plant-food fermentations where hydroxycinnamic acids are abundant. L. plantarum efficiently decarboxylates these compounds, and also reduces them, yielding substituted phenylpropionic acids. Although the reduction step is known to be induced by a hydroxycinnamic acid, the enzymatic machinery responsible for this reduction pathway has not been yet identified and characterized. A previous study on the transcriptomic response of L...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776924/tools-for-rapid-genetic-engineering-of-vibrio-fischeri
#9
Karen L Visick, Kelsey M Hodge-Hanson, Alice H Tischler, Allison K Bennett, Vincent Mastrodomenico
Vibrio fischeri is used as a model for number of processes, including symbiosis, quorum sensing, bioluminescence, and biofilm formation. Many of these studies depend on generating deletion mutants and complementing them. Engineering such strains, however, is a time-consuming, multi-step process that relies on cloning and subcloning. Here, we describe a set of tools that can be used to rapidly engineer deletions and insertions in the V. fischeri chromosome without cloning. We developed a uniform approach for generating deletions using PCR SOEing (Splicing by Overlap Extension) with antibiotic cassettes flanked by standardized linker sequences...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29776923/environmental-adaptability-for-quorum-sensing-regulating-iron-uptake-during-biofilm-formation-in-paracoccus-denitrificans
#10
Yang Zhang, Jie Gao, Lushan Wang, Shuangjiang Liu, Zhihui Bai, Xuliang Zhuang, Guoqiang Zhuang
Paracoccus denitrificans is a valuable model organism due to its versatile respiration capability and bioenergetic flexibility, both of which are critical to its survival in different environments. Quorum sensing (QS) plays a crucial role in the regulation of many cell functions; however, whether QS systems play a role in P. denitrificans is unknown. In this study, we demonstrated that iron uptake systems in P. denitrificans were directly regulated by a newly identified QS system. Genes coding for TonB-dependent systems, which transport chelated iron, were transcribed at higher levels in the QS-defective mutants...
May 18, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752275/whole-genomic-analysis-of-bacillus-thuringiensis-revealing-partial-genes-as-a-source-of-novel-cry-toxins
#11
Muhammad Sajid, Ce Geng, Miaomiao Li, Yueying Wang, Hualin Liu, Jinshui Zheng, Donghai Peng, Ming Sun
Despite the successful application of Crystal proteins (Cry) from Bacillus thuringiensis as biological control agents against insects, there is an increasing demand to identify new Cry toxins having higher toxicity and broad spectrum activity against insects and plant parasitic nematodes. To find novel Cry toxins, we screened 100 whole genome sequences of B. thuringiensis. Surprisingly, in addition to full Cry toxins, we found partial sequences, such as typical N-terminal or C-terminal with conserved domains, widely distributed among 20 strains of B...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752274/molecular-epidemiology-of-shiga-toxin-producing-escherichia-coli-stec-on-new-zealand-dairy-farms-application-of-a-culture-independent-assay-and-whole-genome-sequencing
#12
A Springer Browne, Anne C Midwinter, Helen Withers, Adrian L Cookson, Patrick J Biggs, Jonathan C Marshall, Jackie Benschop, Steve Hathaway, Neville A Haack, Rukhshana N Akhter, Nigel P French
New Zealand has a relatively high incidence of human cases of Shiga toxin-producing Escherichia coli (STEC), with 8.9 STEC cases per 100,000 people reported in 2016. Previous research showed living near cattle and contact with cattle feces as significant risk factors for STEC infections in humans in New Zealand, but infection was not linked to food-associated factors. During the 2014 spring calving season, a random stratified cross-sectional study of dairy farms (n=102) in six regions across New Zealand assessed the prevalence of the 'Top 7' STEC (serogroups O157, O26, O45, O103, O111, O121, O145) in young calves (n=1,508) using a culture-independent diagnostic test (PCR/MALDI-TOF)...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752273/differential-production-of-psl-in-planktonic-cells-leads-to-two-distinctive-attaching-phenotypes-in-pseudomonas-aeruginosa
#13
Shuai Yang, Xinyi Cheng, Zhenyu Jin, Aiguo Xia, Lei Ni, Rongrong Zhang, Fan Jin
Exponentially growing bacteria in a well-mixed planktonic culture are generally assumed to be physiologically and phenotypically uniform, and distinct from their genetically identical counterparts living in biofilms. Using a combination of high spatiotemporal microscopy and a bacterial tracking algorithm, in this study, we showed that the planktonic cells of Pseudomonas aeruginosa differently attach to surfaces even when they remained in the exponential phase. We consistently observed that fast- and slow-attaching phenotypes coexist in planktonic cells, regardless of their growth phase...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752272/functional-profiling-and-crystal-structures-of-isothiocyanate-hydrolases-found-in-gut-associated-and-plant-pathogenic-bacteria
#14
Tijs J M van den Bosch, Kemin Tan, Andrzej Joachimiak, Cornelia U Welte
Isothiocyanates (ITCs) are produced by cruciferous plants to protect them against herbivores and infection by microbes. These compounds are of particular interest due to their antimicrobial and anticarcinogenic properties. The breakdown of ITCs in nature is catalyzed by isothiocyanate hydrolase (ITCase), a novel family within the metallo-β-lactamase-fold superfamily of proteins. saxA genes that code for ITCases are particularly widespread in insect- and plant-associated bacteria. Enzymatic characterization of seven phylogenetically related but distinct ITCases exhibited similar activities on six selected ITCs, suggesting that phylogenetic diversity does not determine the substrate specificity of ITCases...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752271/microbial-mineral-illization-of-montmorillonite-in-low-permeability-oil-reservoirs-for-microbial-enhanced-oil-recovery
#15
Kai Cui, Shanshan Sun, Meng Xiao, Tongjing Liu, Quanshu Xu, Honghong Dong, Di Wang, Yejing Gong, Te Sha, Jirui Hou, Zhongzhi Zhang, Pengcheng Fu
Microbial mineral illization has been investigated for its role in the extraction and recovery of metals from ores. Here we report our application of mineral bioillization for the microbial enhanced oil recovery in low-permeability oil reservoirs. It aimed to reveal the etching mechanism of the four Fe (III)-reducing microbial strains under anaerobic growth conditions on the Ca-montmorillonite. The mineralogical characterization of the Ca-montmorillonite was performed by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy and energy dispersive spectrometer...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752270/the-discovery-of-two-native-baeyer-villiger-monooxygenases-for-asymmetric-synthesis-of-bulky-chiral-sulfoxides
#16
Yan Zhang, Feng Liu, Na Xu, Yin-Qi Wu, Yu-Cong Zheng, Qian Zhao, Guoqiang Lin, Hui-Lei Yu, Jian-He Xu
Two Baeyer-Villiger monooxygenases (BVMOs) designated Bo BVMO and Am BVMO were discovered from Bradyrhizobium oligotrophicum and Aeromicrobium marinum , respectively. Both monooxygenases displayed novel features for catalyzing the asymmetric sulfoxidation of bulky and pharmaceutically relevant thioethers. Evolutionary relationship and sequence analysis revealed that the two BVMOs belong to the family of typical type I BVMO and the subtype ethionamide monooxygenase. Both BVMOs are active toward medium- and long-chain aliphatic ketones as well as various thioether substrates, but ineffective toward cyclohexanone, aromatic ketones and other typical BVMO substrates...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752269/thioredoxin-and-glutaredoxin-systems-required-for-oxidative-stress-resistance-fungicide-sensitivity-and-virulence-of-alternaria-alternata
#17
Haijie Ma, Mingshuang Wang, Yunpeng Gai, Huilan Fu, Bin Zhang, Ruoxin Ruan, Kuang-Ren Chung, Hongye Li
This study determines the function of thioredoxin and glutaredoxin systems in the phytopathogenic fungus Alternaria alternata via analyzing mutants from the targeted deletion of genes encoding thioredoxin peroxidase ( Tsa1 ), thioredoxin reductase ( Trr1 ) and glutathione reductase ( Glr1 ). Trr1 , Glr1 but not Tsa1 are required for growth and conidiation. Reduced growth and conidiation seen in the Trr1 or Glr1 deletion mutant can be restored by glutathione. Deletion mutants showing growth inhibition by oxidants are defective for H2 O2 detoxification and induce smaller lesions on citrus leaves...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752268/preferred-hexoses-influence-long-term-memory-and-induction-of-lactose-catabolism-by-streptococcus-mutans
#18
Lin Zeng, Lulu Chen, Robert A Burne
Bacteria prioritize sugar metabolism via carbohydrate catabolite repression, which regulates global gene expression to optimize the catabolism of preferred substrates. Here, we report an unusual long-term memory effect in certain Streptococcus mutans strains that alters adaptation to growth on lactose after prior exposure to glucose or fructose. In strain GS-5, cells that were first cultured on fructose then transferred to lactose displayed an exceptionally long lag (>11 h) and slower growth, compared to cells first cultured on glucose or cellobiose, which displayed a reduction in lag phase by as much as 10 h...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752267/a-novel-maltogenic-amylase-coma-from-corallococcus-sp-egb-catalyzes-the-conversion-of-maltooligosaccharides-and-soluble-starch-to-maltose
#19
Jie Zhou, Zhoukun Li, Han Zhang, Jiale Wu, Xianfeng Ye, Weiliang Dong, Min Jiang, Yan Huang, Zhongli Cui
Here, a novel amylolytic enzyme gene designated coMA was cloned from Corallococcus sp. EGB. The deduced amino acid sequence contained a predicted lipoprotein signal peptide (residues 1-18) and conserved glycoside hydrolase family 13 (GH13) module. The amino acid sequence of CoMA exhibits low sequence identity (10-19%) with cyclodextrin-hydrolyzing enzymes (GH13_20) and is assigned to GH13_36. The most outstanding feature of CoMA is its ability to catalyze the conversion of maltooligosaccharides (≥ G3) and soluble starch to maltose as the sole hydrolysate...
May 11, 2018: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29752266/biofilm-formation-by-helicobacter-pylori-is-differentially-affected-by-common-culture-conditions-and-protein-plays-a-central-role-in-the-biofilm-matrix
#20
Ian H Windham, Stephanie L Servetas, Jeannette M Whitmire, Daniel Pletzer, Robert E W Hancock, D Scott Merrell
The concept of Helicobacter pylori biofilm formation is relatively new. To help provide a foundation for future biofilm studies, we characterized the biofilm formation ability of a common H. pylori lab strain, G27. The goal of this study was to evaluate biofilm formation by G27 in response to common culture conditions and to explore the biofilm matrix. Our results indicate that while growth in varies types of media did not dramatically effect biofilm formation, surface selection had a significant effect on final biofilm mass...
May 11, 2018: Applied and Environmental Microbiology
journal
journal
26700
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"