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Bacteria evolution

Rekha Seshadri, Sinead C Leahy, Graeme T Attwood, Koon Hoong Teh, Suzanne C Lambie, Adrian L Cookson, Emiley A Eloe-Fadrosh, Georgios A Pavlopoulos, Michalis Hadjithomas, Neha J Varghese, David Paez-Espino, Rechelle Perry, Gemma Henderson, Christopher J Creevey, Nicolas Terrapon, Pascal Lapebie, Elodie Drula, Vincent Lombard, Edward Rubin, Nikos C Kyrpides, Bernard Henrissat, Tanja Woyke, Natalia N Ivanova, William J Kelly
Productivity of ruminant livestock depends on the rumen microbiota, which ferment indigestible plant polysaccharides into nutrients used for growth. Understanding the functions carried out by the rumen microbiota is important for reducing greenhouse gas production by ruminants and for developing biofuels from lignocellulose. We present 410 cultured bacteria and archaea, together with their reference genomes, representing every cultivated rumen-associated archaeal and bacterial family. We evaluate polysaccharide degradation, short-chain fatty acid production and methanogenesis pathways, and assign specific taxa to functions...
March 19, 2018: Nature Biotechnology
Qusay Abdoh, Lubna Kharraz, Khubaib Ayoub, Jana Khraim, Wafaa Awad, Aysha Sbeah, Safaa Turman
BACKGROUND: Bacterial resistance to antibiotics is considered the most important determinant of treatment failure. Monitoring the evolution of antimicrobial resistance to common antibiotics is therefore of special importance for clinicians. The frequency of resistance to antibiotics in Helicobacter pylori isolates is increasing. The aim of this study was to determine the pattern of H pylori antibiotic resistance at the An-Najah National University Hospital. METHODS: In this cross-sectional study, we recruited patients older than 18 year who were admitted to the An-Najah National University Hospital...
February 21, 2018: Lancet
Qinglan Guo, Mustapha M Mustapha, Mingliang Chen, Di Qu, Xi Zhang, Min Chen, Yohei Doi, Minggui Wang, Lee H Harrison
The expansion of hypervirulent sequence type 4821 clonal complex (CC4821) lineage Neisseria meningitidis bacteria has led to a shift in meningococcal disease epidemiology in China, from serogroup A (MenA) to MenC. Knowledge of the evolution and genetic origin of the emergent MenC strains is limited. In this study, we subjected 76 CC4821 isolates collected across China during 1972-1977 and 2005-2013 to phylogenetic analysis, traditional genotyping, or both. We show that successive recombination events within genes encoding surface antigens and acquisition of quinolone resistance mutations possibly played a role in the emergence of CC4821 as an epidemic clone in China...
April 2018: Emerging Infectious Diseases
Cássia Oliveira, Lauren Gunderman, Cathryn A Coles, Jason Lochmann, Megan Parks, Ethan Ballard, Galina Glazko, Yasir Rahmatallah, Alan J Tackett, David J Thomas
The microbial diversity within cave ecosystems is largely unknown. Ozark caves maintain a year-round stable temperature (12-14 °C), but most parts of the caves experience complete darkness. The lack of sunlight and geological isolation from surface-energy inputs generate nutrient-poor conditions that may limit species diversity in such environments. Although microorganisms play a crucial role in sustaining life on Earth and impacting human health, little is known about their diversity, ecology, and evolution in community structures...
September 2017: Diversity
Nami Matsumoto, Hiromi Hattori, Minenosuke Matsutani, Chihiro Matayoshi, Hirohide Toyama, Naoya Kataoka, Toshiharu Yakushi, Kazunobu Matsushita
Thermotolerant microorganisms are beneficial to the fermentation industry because of a reduction in cooling efforts and other operational advantages. Previously, we have obtained a thermally adapted Gluconobacter frateurii strain by experimental evolution. In the present study, we found only a single G insertion in the adapted strain, which causes a frameshift in a gene encoding a putative drug transporter. A mutant derivative strain with the single G insertion in the transporter gene (Wild-G) was constructed from the wild-type strain and showed increased thermotolerance...
March 16, 2018: Applied and Environmental Microbiology
Teresa Morales-Ruiz, Álvaro C Romero-Valenzuela, Vanessa M Vázquez-Grande, Teresa Roldán-Arjona, Rafael R Ariza, Dolores Córdoba-Cañero
Base excision repair (BER) is a major defense pathway against spontaneous DNA damage. This multistep process is initiated by DNA glycosylases that recognise and excise the damaged base, and proceeds by the concerted action of additional proteins that perform incision of the abasic site, gap filling and ligation. BER has been extensively studied in bacteria, yeasts and animals. Although knowledge of this pathway in land plants is increasing, there are no reports detecting BER in algae. We describe here an experimental in vitro system allowing the specific analysis of BER in the model alga Chlamydomonas reinhardtii...
March 5, 2018: DNA Repair
Edward J Steele, Shirwan Al-Mufti, Kenneth A Augustyn, Rohana Chandrajith, John P Coghlan, S G Coulson, Sudipto Ghosh, Mark Gillman, Reginald M Gorczynski, Brig Klyce, Godfrey Louis, Kithsiri Mahanama, Keith R Oliver, Julio Padron, Jiangwen Qu, John A Schuster, W E Smith, Duane P Snyder, Julian A Steele, Brent J Stewart, Robert Temple, Gensuke Tokoro, Christopher A Tout, Alexander Unzicker, Milton Wainwright, Jamie Wallis, Daryl H Wallis, Max K Wallis, John Wetherall, D T Wickramasinghe, J T Wickramasinghe, N Chandra Wickramasinghe, Yongsheng Liu
We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H- W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events...
March 12, 2018: Progress in Biophysics and Molecular Biology
Michael W Deem, Melia Elizabeth Bonomo
Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (Cas) constitute a multi-functional, constantly evolving immune system in bacteria and archaea cells. A heritable, molecular memory is generated of phage, plasmids, or other mobile genetic elements that attempt to attack the cell. This memory is used to recognize and interfere with subsequent invasions from the same genetic elements. This versatile prokaryotic tool has also been used to advance applications in biotechnology...
March 15, 2018: Physical Biology
Paulo André Dias Bastos, Lúcio Lara Santos, Rui Miguel Pinheiro Vitorino
The human gut barrier is the tissue exposed to the highest load of microorganisms, harbouring 100 trillion bacteria. In addition, the gut's renewal rate outruns that of any other human tissue. Antimicrobial peptides (AMPs) are highly optimized defense molecules in the intestinal barrier optimized to maintain gastrointestinal homeostasis. Alterations in AMPs activity can lead to or result from human gastrointestinal diseases. In this review, unique, conserved, or otherwise regular alterations in the expression patterns of human AMPs across gastrointestinal inflammatory and infectious diseases were analyzed for pattern elucidation...
March 2018: Journal of Peptide Science: An Official Publication of the European Peptide Society
Eleni C Pappa, Thomas G Bontinis, Maria Tasioula-Margari, John Samelis
The microbiological quality of and changes in the main physicochemical parameters, together with the evolution of proteolysis, lipolysis and volatile profiles of soft Xinotyri, a traditional Greek acid-curd cheese (pH≈4.4, moisture 65%, salt 1%) made from raw (RMC) or pasteurized (PMC) goat's milk without starters, were evaluated during aerobic storage at 4o C for 60 days. No statistically significant differences between the total nitrogen (TN) and nitrogen fraction (% of TN) contents, the degradation of intact αs - or β-caseins, total free amino acid (FAA) contents, and the ratio of hydrophilic and hydrophobic peptides in the water-soluble fraction of RMC and PMC were found...
December 2017: Food Technology and Biotechnology
Verity A Jackson, Dimphna H Meijer, Maria Carrasquero, Laura S van Bezouwen, Edward D Lowe, Colin Kleanthous, Bert J C Janssen, Elena Seiradake
Teneurins are ancient cell-cell adhesion receptors that are vital for brain development and synapse organisation. They originated in early metazoan evolution through a horizontal gene transfer event when a bacterial YD-repeat toxin fused to a eukaryotic receptor. We present X-ray crystallography and cryo-EM structures of two Teneurins, revealing a ~200 kDa extracellular super-fold in which eight sub-domains form an intricate structure centred on a spiralling YD-repeat shell. An alternatively spliced loop, which is implicated in homophilic Teneurin interaction and specificity, is exposed and thus poised for interaction...
March 14, 2018: Nature Communications
Dilruba Sharmin, Yong Guo, Tomoyasu Nishizawa, Shoko Ohshima, Yoshinori Sato, Yusuke Takashima, Kazuhiko Narisawa, Hiroyuki Ohta
Endohyphal bacteria (EHB), dwelling within fungal hyphae, markedly affect the growth and metabolic potential of their hosts. To date, two EHB belonging to the family Burkholderiaceae have been isolated and characterized as new taxa, Burkholderia rhizoxinica (HKI 454T ) and Mycoavidus cysteinexigens (B1-EBT ), in Japan. Metagenome sequencing was recently reported for Mortierella elongata AG77 together with its endosymbiont M. cysteinexigens (Mc-AG77) from a soil/litter sample in the USA. In the present study, we elucidated the complete genome sequence of B1-EBT and compared it with those of Mc-AG77 and HKI 454T ...
March 14, 2018: Microbes and Environments
Guozhi Yu, Desiree Y Baeder, Roland R Regoes, Jens Rolff
Antibiotic resistance constitutes one of the most pressing public health concerns. Antimicrobial peptides (AMPs) of multicellular organisms are considered part of a solution to this problem, and AMPs produced by bacteria such as colistin are last-resort drugs. Importantly, AMPs differ from many antibiotics in their pharmacodynamic characteristics. Here we implement these differences within a theoretical framework to predict the evolution of resistance against AMPs and compare it to antibiotic resistance. Our analysis of resistance evolution finds that pharmacodynamic differences all combine to produce a much lower probability that resistance will evolve against AMPs...
March 14, 2018: Proceedings. Biological Sciences
Mariia Rabyk, Oleksandr Yushchuk, Ihor Rokytskyy, Maria Anisimova, Bohdan Ostash
The AdpA protein from a streptomycin producer Streptomyces griseus is a founding member of the AdpA family of pleiotropic regulators, known to be ubiquitously present in streptomycetes. Functional genomic approaches revealed a huge number of AdpA targets, leading to the claim that the AdpA regulon is the largest one in bacteria. The expression of adpA is limited at the level of translation of the rare leucyl UUA codon. All known properties of AdpA regulators were discovered on a few streptomycete strains. There are open questions about the true abundance and diversity of AdpA across actinobacterial taxa (and beyond) and about the possible evolutionary forces that shape the AdpA orthologous group in Streptomyces...
March 13, 2018: Journal of Molecular Evolution
Karissa L Cross, Payal Chirania, Weili Xiong, Clifford J Beall, James G Elkins, Richard J Giannone, Ann L Griffen, Adam M Guss, Robert L Hettich, Snehal S Joshi, Elaine M Mokrzan, Roman K Martin, Igor B Zhulin, Eugene J Leys, Mircea Podar
The human oral microbiota encompasses representatives of many bacterial lineages that have not yet been cultured. Here we describe the isolation and characterization of previously uncultured Desulfobulbus oralis , the first human-associated representative of its genus. As mammalian-associated microbes rarely have free-living close relatives, D. oralis provides opportunities to study how bacteria adapt and evolve within a host. This sulfate-reducing deltaproteobacterium has adapted to the human oral subgingival niche by curtailing its physiological repertoire, losing some biosynthetic abilities and metabolic independence, and by dramatically reducing environmental sensing and signaling capabilities...
March 13, 2018: MBio
Claudia C Paredes-Amaya, Gilberto Valdés-García, Víctor R Juárez-González, Enrique Rudiño-Piñera, Víctor H Bustamante
HilD is an AraC-like transcriptional regulator that plays a central role in Salmonella virulence. HilD controls the expression of the genes within the Salmonella pathogenicity island 1 (SPI-1) and of several genes located outside SPI-1, which are mainly required for Salmonella invasion of host cells. The expression, amount and activity of HilD are tightly controlled by the activities of several factors. The HilE protein represses the expression of the SPI-1 genes through its interaction with HilD; however, the mechanism by which HilE affects HilD is unknown...
March 13, 2018: Journal of Biological Chemistry
Raphaël Méheust, Debashish Bhattacharya, Jananan S Pathmanathan, James O McInerney, Philippe Lopez, Eric Bapteste
BACKGROUND: Eukaryotes evolved from the symbiotic association of at least two prokaryotic partners, and a good deal is known about the timings, mechanisms, and dynamics of these evolutionary steps. Recently, it was shown that a new class of nuclear genes, symbiogenetic genes (S-genes), was formed concomitant with endosymbiosis and the subsequent evolution of eukaryotic photosynthetic lineages. Understanding their origins and contributions to eukaryogenesis would provide insights into the ways in which cellular complexity has evolved...
March 13, 2018: BMC Biology
Kati Saarinen, Jouni Laakso, Leena Lindström, Tarmo Ketola
Rapid environmental fluctuations are ubiquitous in the wild, yet majority of experimental studies mostly consider effects of slow fluctuations on organism. To test the evolutionary consequences of fast fluctuations, we conducted nine independent experimental evolution experiments with bacteria. Experimental conditions were same for all species, and we allowed them to evolve either in fluctuating temperature alternating rapidly between 20°C and 40°C or at constant 30°C temperature. After experimental evolution, we tested the performance of the clones in both rapid fluctuation and in constant environments (20°C, 30°C and 40°C)...
March 2018: Ecology and Evolution
Tong Tong, Si Chen, Lianrong Wang, You Tang, Jae Yong Ryu, Susu Jiang, Xiaolin Wu, Chao Chen, Jie Luo, Zixin Deng, Zhiqiang Li, Sang Yup Lee, Shi Chen
The chemical diversity of physiological DNA modifications has expanded with the identification of phosphorothioate (PT) modification in which the nonbridging oxygen in the sugar-phosphate backbone of DNA is replaced by sulfur. Together with DndFGH as cognate restriction enzymes, DNA PT modification, which is catalyzed by the DndABCDE proteins, functions as a bacterial restriction-modification (R-M) system that protects cells against invading foreign DNA. However, the occurrence of dnd systems across a large number of bacterial genomes and their functions other than R-M are poorly understood...
March 12, 2018: Proceedings of the National Academy of Sciences of the United States of America
Dal-Hoe Koo, William T Molin, Christopher A Saski, Jiming Jiang, Karthik Putta, Mithila Jugulam, Bernd Friebe, Bikram S Gill
Gene amplification has been observed in many bacteria and eukaryotes as a response to various selective pressures, such as antibiotics, cytotoxic drugs, pesticides, herbicides, and other stressful environmental conditions. An increase in gene copy number is often found as extrachromosomal elements that usually contain autonomously replicating extrachromosomal circular DNA molecules (eccDNAs). Amaranthus palmeri , a crop weed, can develop herbicide resistance to glyphosate [ N -(phosphonomethyl) glycine] by amplification of the 5-enolpyruvylshikimate-3-phosphate synthase ( EPSPS ) gene, the molecular target of glyphosate...
March 12, 2018: Proceedings of the National Academy of Sciences of the United States of America
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