A flow-cytometric gram-staining technique for milk-associated bacteria.
AuthorsHolm C, Jespersen L
JournalAppl Environ Microbiol
PubMed ID12732558
'A Gram-staining technique combining staining with two fluorescent stains, Oregon Green-conjugated wheat germ agglutinin (WGA) and hexidium iodide (HI) followed by flow-cytometric detection is described. WGA stains gram-positive bacteria while HI binds to the DNA of all bacteria after permeabilization by EDTA and incubation at 50 degrees C for 15 ... More
Endopeptidase penicillin-binding proteins 4 and 7 play auxiliary roles in determining uniform morphology of Escherichia coli.
AuthorsMeberg BM, Paulson AL, Priyadarshini R, Young KD,
JournalJ Bacteriol
PubMed ID15576782
'The low-molecular-weight (LMW) penicillin-binding protein, PBP 5, plays a dominant role in determining the uniform cell shape of Escherichia coli. However, the physiological functions of six other LMW PBPs are unknown, even though the existence and enzymatic activities of four of these were established three decades ago. By applying fluorescence-activated ... More
Genetic diversity of viable, injured, and dead fecal bacteria assessed by fluorescence-activated cell sorting and 16S rRNA gene analysis.
AuthorsBen-Amor K, Heilig H, Smidt H, Vaughan EE, Abee T, de Vos WM,
JournalAppl Environ Microbiol
PubMed ID16085863
'A novel approach combining a flow cytometric in situ viability assay with 16S rRNA gene analysis was used to study the relationship between diversity and activity of the fecal microbiota. Simultaneous staining with propidium iodide (PI) and SYTO BC provided clear discrimination between intact cells (49%), injured or damaged cells ... More
Roles of cellular activation and sulfated glycans in Haemophilus somnus adherence to bovine brain microvascular endothelial cells.
AuthorsBehling-Kelly E, Vonderheid H, Kim KS, Corbeil LB, Czuprynski CJ,
JournalInfect Immun
PubMed ID16926425
'Haemophilus somnus can cause a devastating fibrinopurulent meningitis with thrombotic vasculitis and encephalitis in cattle. The mechanisms used by H. somnus to migrate from the bloodstream into the central nervous system (CNS) are unknown. In this study, we demonstrate that H. somnus adheres to, but does not invade, bovine brain ... More
Space flight alters bacterial gene expression and virulence and reveals a role for global regulator Hfq.
AuthorsWilson JW, Ott CM, Höner zu Bentrup K, Ramamurthy R, Quick L, Porwollik S, Cheng P, McClelland M, Tsaprailis G, Radabaugh T, Hunt A, Fernandez D, Richter E, Shah M, Kilcoyne M, Joshi L, Nelman-Gonzalez M, Hing S, Parra M, Dumars P, Norwood K, Bober R, Devich J, Ruggles A, Goulart C, Rupert M, Stodieck L, Stafford P, Catella L, Schurr MJ, Buchanan K, Morici L, McCracken J, Allen P, Baker-Coleman C, Hammond T, Vogel J, Nelson R, Pierson DL, Stefanyshyn-Piper HM, Nickerson CA,
JournalProc Natl Acad Sci U S A
PubMed ID17901201
'A comprehensive analysis of both the molecular genetic and phenotypic responses of any organism to the space flight environment has never been accomplished because of significant technological and logistical hurdles. Moreover, the effects of space flight on microbial pathogenicity and associated infectious disease risks have not been studied. The bacterial ... More
Development of a flow cytometric method to analyze subpopulations of bacteria in probiotic products and dairy starters.
AuthorsBunthof CJ, Abee T
JournalAppl Environ Microbiol
PubMed ID12039752
'Flow cytometry (FCM) is a rapid and sensitive technique that can determine cell numbers and measure various physiological characteristics of individual cells by using appropriate fluorescent probes. Previously, we developed an FCM assay with the viability probes carboxyfluorescein diacetate (cFDA) and TOTO-1 [1''-(4,4,7,7-tetramethyl-4,7-diazaundecamethylene)-bis-4-[3-methyl-2,3dihydro(benzo-1,3-oxazole)-2-methylidene]-1-(3''-trimethylammoniumpropyl)-pyridinium tetraiodide] for (stressed) lactic acid bacteria (C. ... More
Sperm quality assessments for endangered razorback suckers Xyrauchen texanus.
'Flow cytometry (FCM) and computer-assisted sperm motion analysis (CASA) methods were developed and validated for use with endangered razorback suckers Xyrauchen texanus collected (n=64) during the 2006 spawning season. Sperm motility could be activated within osmolality ranges noted during milt collections (here 167-343?mOsm/kg). We hypothesized that sperm quality of milt ... More
Evidence for direct electron transfer by a gram-positive bacterium isolated from a microbial fuel cell.
AuthorsWrighton KC, Thrash JC, Melnyk RA, Bigi JP, Byrne-Bailey KG, Remis JP, Schichnes D, Auer M, Chang CJ, Coates JD,
JournalAppl Environ Microbiol
PubMed ID21908627
'Despite their importance in iron redox cycles and bioenergy production, the underlying physiological, genetic, and biochemical mechanisms of extracellular electron transfer by Gram-positive bacteria remain insufficiently understood. In this work, we investigated respiration by Thermincola potens strain JR, a Gram-positive isolate obtained from the anode surface of a microbial fuel ... More
Adaptation in a mouse colony monoassociated with Escherichia coli K-12 for more than 1,000 days.
AuthorsLee SM, Wyse A, Lesher A, Everett ML, Lou L, Holzknecht ZE, Whitesides JF, Spears PA, Bowles DE, Lin SS, Tonkonogy SL, Orndorff PE, Bollinger RR, Parker W,
JournalAppl Environ Microbiol
PubMed ID20472724
Although mice associated with a single bacterial species have been used to provide a simple model for analysis of host-bacteria relationships, bacteria have been shown to display adaptability when grown in a variety of novel environments. In this study, changes associated with the host-bacterium relationship in mice monoassociated with Escherichia ... More
The Escherichia coli mqsR and ygiT genes encode a new toxin-antitoxin pair.
AuthorsKasari V, Kurg K, Margus T, Tenson T, Kaldalu N,
JournalJ Bacteriol
PubMed ID20233923
Toxin-antitoxin (TA) systems are plasmid- or chromosome-encoded protein complexes composed of a stable toxin and a short-lived inhibitor of the toxin. In cultures of Escherichia coli, transcription of toxin-antitoxin genes was induced in a nondividing subpopulation of bacteria that was tolerant to bactericidal antibiotics. Along with transcription of known toxin-antitoxin ... More
Response of gut microbiota to fasting and hibernation in Syrian hamsters.
AuthorsSonoyama K, Fujiwara R, Takemura N, Ogasawara T, Watanabe J, Ito H, Morita T,
JournalAppl Environ Microbiol
PubMed ID19700553
Although hibernating mammals wake occasionally to eat during torpor, this period represents a state of fasting. Fasting is known to alter the gut microbiota in nonhibernating mammals; therefore, hibernation may also affect the gut microbiota. However, there are few reports of gut microbiota in hibernating mammals. The present study aimed ... More
The role of complement C3 opsonization, C5a receptor, and CD14 in E. coli-induced up-regulation of granulocyte and monocyte CD11b/CD18 (CR3), phagocytosis, and oxidative burst in human whole blood.
AuthorsBrekke OL, Christiansen D, Fure H, Fung M, Mollnes TE,
JournalJ Leukoc Biol
PubMed ID17389579
The relative role of complement and CD14 in Escherichia coli-induced leukocyte CD11b up-regulation, phagocytosis, and oxidative burst in human whole blood was examined. The highly specific thrombin inhibitor lepirudin was used as anticoagulant, as it does not affect complement activation. Complement inhibition at the level of C3 (anti-C2 and anti-factor ... More