Read by QxMD icon Read

Journal of Bacteriology

Thomas J Silhavy
The Journal of Bacteriology (JB) is a prestigious periodical that publishes research articles that probe fundamental processes in bacteria, archaea, and their viruses, and the molecular mechanisms by which they interact with each other and with their hosts and their environments.….
November 5, 2018: Journal of Bacteriology
M Bartolini, S Cogliati, D Vileta, C Bauman, L Rateni, C Leñini, F Argañaraz, M Francisco, J M Villalba, L Steil, U Völker, R Grau
Bacterial biofilms are important in natural settings, biotechnology and medicine. However, regulation of biofilm development and its persistence in different niches is complex and only partially understood. One key step during the biofilm life cycle is dispersal, when motile cells abandon the mature biofilm to spread out and colonize new niches. Here, we show that in the model bacterium Bacillus subtilis the general stress transcription factor SigB is essential for halting detrimental overgrowth of mature biofilm and for triggering dispersal when nutrients become limited...
November 5, 2018: Journal of Bacteriology
Nicholas A Wood, Krystal Chung, Amanda Blocker, Nathalia Rodrigues de Almeida, Martin Conda-Sheridan, Derek J Fisher, Scot P Ouellette
Chlamydia is an obligate intracellular bacterium that differentiates between two distinct functional and morphological forms during its developmental cycle: elementary bodies (EBs) and reticulate bodies (RBs). EBs are non-dividing, small electron dense forms that infect host cells. RBs are larger, non-infectious replicative forms that develop within a membrane-bound vesicle, termed an inclusion. Given the unique properties of each developmental form of this bacterium, we hypothesized that the Clp protease system plays an integral role in proteomic turnover by degrading specific proteins from one developmental form or the other...
November 5, 2018: Journal of Bacteriology
Ronald F Peck, Serena M Graham, Abby M Gregory
Halophilic Archaea are a distinctive pink color due to a carotenoid pigment called bacterioruberin. To sense or utilize light, many halophilic Archaea also produce rhodopsins, complexes of opsin proteins with a retinal prosthetic group. Both bacterioruberin and retinal are synthesized from isoprenoid precursors with lycopene as the last shared intermediate. We previously described a regulatory mechanism in which Halobacterium salinarum bacterioopsin and Haloarcula vallismortis cruxopsin, respectively, inhibit bacterioruberin synthesis catalyzed by lycopene elongase...
October 29, 2018: Journal of Bacteriology
Tamiko Oguri, Youjeong Kwon, Jerry K K Woo, Gerd Prehna, Hyun Lee, Miaoran Ning, Kyoung-Jae Won, Jiyoung Lee, Sally Mei, Yixin Shi, Hyunyoung Jeong, Hyunwoo Lee
By screening a collection of Salmonella mutants deleted for genes encoding small proteins ≤60 amino acids, we identified three paralogous small genes ( ymdF , STM14_1829 , and yciG ) required for wild-type flagella-dependent swimming and swarming motility. The ymdF , STM14_1829, and yciG genes encode small proteins of 55, 60, and 60 amino-acid residues, respectively. Bioinformatics analysis predicted that these small proteins are intrinsically disordered proteins, and circular dichroism analysis of purified recombinant proteins confirmed that all three proteins are unstructured in solution...
October 29, 2018: Journal of Bacteriology
Valentina Godovikova, M Paula Goetting-Minesky, John C Timm, J Christopher Fenno
Treponema denticola , one of several recognized periodontal pathogens, is a model organism for studying Treponema physiology and host-microbe interactions. Its major surface protein Msp (or MOSP) comprises an oligomeric outer membrane-associated complex that binds fibronectin, has cytotoxic pore-forming activity and disrupts several intracellular responses. There are two hypotheses regarding native Msp structure and membrane topology. One hypothesis predicts that the entire Msp protein forms a ß-barrel structure similar to well-studied outer membrane porins of Gram-negative bacteria...
October 29, 2018: Journal of Bacteriology
Jeffrey A Cole
Hexuronic acids, oxidation products of common sugars, are widespread in eukaryotic cells. Galacturonic acid is the main carbohydrate component of pectin found in plant cell walls and glucuronic acid is a component of proteoglycans in animals. However, despite their importance as carbohydrate substrates, metabolism of hexuronic acids has long remained a poorly studied corner of the bacterial metabolic map. In the current issue of Journal of Bacteriology , Bouvier and coworkers present a detailed analysis of genes involved in hexuronate utilization in various proteobacteria and verify their bioinformatics predictions by carefully designed experiments (Bouvier JT, Sernova NV, Ghasempur S, Rodionova IA, Vetting MW, Al-Obaidi NF, Almo SC, Gerlt JA, Rodionov DA...
October 29, 2018: Journal of Bacteriology
Lin Zeng, Robert A Burne
The dental caries pathogen Streptococcus mutans can ferment a variety of sugars to produce organic acids. Exposure of S. mutans to certain non-metabolizable carbohydrates such as xylitol impairs growth and can cause cell death. Recently, the presence of a sugar-phosphate stress in S. mutans was demonstrated using a mutant lacking 1-phosphofructokinase (FruK) that accumulates fructose-1-phosphate (F-1-P). Here we studied an operon in S. mutans , sppRA, which was highly expressed in the fruK mutant. Biochemical characterization of a recombinant SppA protein indicated that it possessed hexose-phosphate phosphohydrolase activity, with preferences for F-1-P and, to a lesser degree, fructose-6-phosphate (F-6-P)...
October 22, 2018: Journal of Bacteriology
Carly Ching, Brendan Yang, Chineme Onwubueke, David Lazinski, Andrew Camilli, Veronica G Godoy
Acinetobacter baumannii is a Gram-negative opportunistic pathogen known to survive harsh environmental conditions and is a leading cause of hospital-acquired infections. Specifically, multicellular communities, known as biofilms, of A. baumannii can withstand desiccation and survive on hospital surfaces and equipment. Biofilms are bacteria embedded in a self-produced extracellular matrix composed of proteins, sugars and/or DNA. Bacteria in a biofilm are protected from environmental stress, including antibiotics, providing them with selective advantage for survival...
October 22, 2018: Journal of Bacteriology
James S Orr, David G Christensen, Alan J Wolfe, Christopher V Rao
Escherichia coli produces acetate during aerobic growth on various carbon sources. Following consumption of the carbon substrate, E. coli can further grow on the acetate. This phenomenon is known as the acetate switch, where cells transition from producing acetate to consuming it. In this study, we investigated how pH governs the acetate switch. When E. coli was grown on a glucose-supplemented medium initially buffered to pH 7, the cells produced and then consumed the acetate. However, when the initial pH was dropped to 6, the cells still produced acetate but were only able to consume it when little (<10 mM) acetate was produced...
October 22, 2018: Journal of Bacteriology
Johanna Heuveling, Heidi Landmesser, Erwin Schneider
The histidine ATP-binding cassette (ABC) transporter of Salmonella enterica serovar Typhimurium is among the best-studied type I ABC import systems. The transporter consists of two transmembrane subunits, HisQ and HisM, and a homodimer of the nucleotide-binding subunit, HisP. Substrates are delivered by two periplasmic solute binding proteins, HisJ and LAO, with preferences for histidine and lysine, arginine, ornithine, respectively. A homology model was built by using the arginine-bound crystal structure of the closely related Art(QN)2 transporter of Thermoanaerobacter tengcongensis as template...
October 22, 2018: Journal of Bacteriology
Kelly M Storek, Rajesh Vij, Dawei Sun, Peter A Smith, James T Koerber, Steven T Rutherford
Integral β-barrel membrane proteins are folded and inserted into the Gram-negative bacterial outer membrane by the β-barrel assembly machine (BAM). This essential complex, comprised of a β-barrel protein, BamA, and four lipoproteins, BamB, BamC, BamD, and BamE, resides in the outer membrane, a unique asymmetrical lipid bilayer that is difficult to recapitulate in vitro Thus, probing BAM function in living cells is critical to fully understand the mechanism of β-barrel folding. We recently identified an α-BamA monoclonal antibody, MAB1, that is a specific and potent inhibitor of BamA function...
October 15, 2018: Journal of Bacteriology
Donald Oliver
Characterization of Sec-dependent bacterial protein transport has often relied on an in vitro protein translocation system comprised in part of E. coli inverted inner membrane vesicles or more recently purified SecYEG translocons reconstituted into liposomes using mostly a single substrate (proOmpA). A paper published in this issue of the Journal of Bacteriology (P. Bariya and L. Randall, J Bacteriol, this issue) finds that inclusion of SecA protein during SecYEG proteoliposome reconstitution dramatically improves the number of active translocons: both an experimentally useful and intriguing result that may arise from SecA membrane integration properties as discussed here...
October 15, 2018: Journal of Bacteriology
Jun Lu, Yun Peng, Sereana Wan, Laura S Frost, Tracy Raivio, J N Mark Glover
The F plasmid tra operon encodes most of the proteins required for bacterial conjugation. TraJ and ArcA are known activators of the tra operon promoter PY which is subject to H-NS-mediated silencing. Donor ability and promoter activity assays indicated that PY is inactivated by silencers and requires both TraJ and ArcA for activation to support efficient F conjugation. The observed low-level, ArcA-independent F conjugation is caused by tra expression from upstream alternative promoters. Electrophoretic mobility shift assays showed that TraJ alone weakly binds to PY regulatory DNA; however, TraJ binding is significantly enhanced by ArcA binding to the same DNA, indicating cooperativity of the two proteins...
October 15, 2018: Journal of Bacteriology
Eleni Karinou, Christopher F Schuster, Manuel Pazos, Waldemar Vollmer, Angelika Gründling
The cell wall of Staphylococcus aureus is composed of peptidoglycan and the anionic polymers lipoteichoic acid (LTA) and wall teichoic acid. LTA is required for growth and normal cell morphology in S. aureus Strains lacking LTA are usually only viable when grown under osmotically stabilizing conditions or after the acquisition of compensatory mutations. LTA negative suppressor strains with inactivating mutations in gdpP , resulting in an increase in intracellular c-di-AMP levels, have been described previously...
October 15, 2018: Journal of Bacteriology
Roy Al Ahmar, Brandon D Kirby, Hongwei D Yu
Mucoidy due to alginate overproduction by the Gram-negative bacterium Pseudomonas aeruginosa facilitates chronic lung infections in patients with Cystic Fibrosis (CF). We previously reported that disruption in de novo synthesis of pyrimidines resulted in conversion to a non-mucoid small colony variant (SCV) in the mucoid P. aeruginosa strain (PAO581), which has a truncated anti-sigma factor MucA25 that cannot sequester sigma factor AlgU/T. Here we showed that supplementation with the nitrogenous bases uracil or cytosine in growth medium complemented SCV to normal growth, and non-mucoidy to mucoidy in these mucA25 mutants...
October 15, 2018: Journal of Bacteriology
Sara R Palmer, Zhi Ren, Geelsu Hwang, Yuan Liu, Ashton Combs, Bill Söderström, Patricia Lara Vasquez, Yalda Khosravi, L Jeannine Brady, Hyun Koo, Paul Stoodley
Proper envelope biogenesis of Streptococcus mutans , a biofilm-forming and dental caries causing oral pathogen, requires two paralogs ( yidC1 and yidC2 ) of the universally conserved YidC/Oxa1/Alb3 family of membrane integral chaperones and insertases. Deletion of either paralog attenuates virulence in vivo but the mechanisms of disruption remain unclear. Here, we determined whether deletion of yidC affects cell surface properties, extracellular glucan production, and/or the structural organization of EPS matrix and biophysical properties of S...
October 15, 2018: Journal of Bacteriology
Nelson Wang, Jan Haug Anonsen, Raimonda Viburiene, Joseph S Lam, Åshild Vik, Michael Koomey
The genus Neisseria includes three major species of importance to human health and disease ( Neisseria gonorrhoeae , N. meningitidis , and N. lactamica ) that express broad spectrum O -linked protein glycosylation systems. The potential for related pgl systems in other species in the genus, however, remains to be determined. Using a strain of N. elongata subsp. glycolytica , a unique tetrasaccharide glycoform consisting of di- N -acetylbacillosamine and glucose as the first two sugars followed by a rare sugar whose mass spectrometric fragmentation profile was most consistent with di- N -acetyl hexuronic acid and a N -acetylhexosamine at the non-reducing end has been identified...
October 15, 2018: Journal of Bacteriology
Arnab Basu, Kate E Shields, Christopher S Eickhoff, Daniel F Hoft, Mee-Ngan F Yap
The translationally silent 100S ribosome is a poorly understood form of the dimeric 70S complex that is ubiquitously found in all bacterial phyla. Eliminating the hibernating 100S ribosome leads to translational derepression, ribosome instability, antibiotic sensitivity, and biofilm defects in some bacteria. In Firmicutes, such as the opportunistic pathogen Staphylococcus aureus , a 190-amino acids protein called <u>h</u> ibernating- <u>p</u> romoting <u>f</u> actor (HPF) dimerizes and conjoins two 70S ribosomes through a direct interaction between the HPF homodimer, with each HPF monomer tethered on an individual 70S complex...
October 8, 2018: Journal of Bacteriology
Raphael H Valdivia, Robert J Bastidas
Chlamydia has emerged as an important model system for the study of host pathogen interactions, in part due to a resurgence in the development of tools for its molecular genetic manipulation. An additional tool, published by Keb et al (2018)., now allows for custom genetic engineering of genomic regions that were traditionally recalcitrant to genetic manipulation, such as genes within operons. This new method will be an essential instrument for dissection of Chlamydia host interactions.
October 8, 2018: Journal of Bacteriology
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"