Abstract:
:Bacteria of the genus Prosthecobacter express homologs of eukaryotic α- and β-tubulin, called BtubA and BtubB (BtubA/B), that have been observed to assemble into filaments in the presence of GTP. BtubA/B polymers are proposed to be composed in vitro by two to six protofilaments in contrast to that in vivo, where they have been reported to form 5-protofilament tubes named bacterial microtubules (bMTs). The btubAB genes likely entered the Prosthecobacter lineage via horizontal gene transfer and may be derived from an early ancestor of the modern eukaryotic microtubule (MT). Previous biochemical studies revealed that BtubA/B polymerization is reversible and that BtubA/B folding does not require chaperones. To better understand BtubA/B filament behavior and gain insight into the evolution of microtubule dynamics, we characterized in vitro BtubA/B assembly using a combination of polymerization kinetics assays and microscopy. Like eukaryotic microtubules, BtubA/B filaments exhibit polarized growth with different assembly rates at each end. GTP hydrolysis stimulated by BtubA/B polymerization drives a stochastic mechanism of filament disassembly that occurs via polymer breakage and/or fast continuous depolymerization. We also observed treadmilling (continuous addition and loss of subunits at opposite ends) of BtubA/B filament fragments. Unlike MTs, polymerization of BtubA/B requires KCl, which reduces the critical concentration for BtubA/B assembly and induces it to form stable mixed-orientation bundles in the absence of any additional BtubA/B-binding proteins. The complex dynamics that we observe in stabilized and unstabilized BtubA/B filaments may reflect common properties of an ancestral eukaryotic tubulin polymer.IMPORTANCE Microtubules are polymers within all eukaryotic cells that perform critical functions; they segregate chromosomes, organize intracellular transport, and support the flagella. These functions rely on the remarkable range of tunable dynamic behaviors of microtubules. Bacterial tubulin A and B (BtubA/B) are evolutionarily related proteins that form polymers. They are proposed to be evolved from the ancestral eukaryotic tubulin, a missing link in microtubule evolution. Using microscopy and biochemical approaches to characterize BtubA/B assembly in vitro, we observed that they exhibit complex and structurally polarized dynamic behavior like eukaryotic microtubules but differ in how they self-associate into bundles and how this bundling affects their stability. Our results demonstrate the diversity of mechanisms through which tubulin homologs promote filament dynamics and monomer turnover.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Díaz-Celis C,Risca VI,Hurtado F,Polka JK,Hansen SD,Maturana D,Lagos R,Mullins RD,Monasterio Odoi
10.1128/JB.00211-17subject
Has Abstractpub_date
2017-09-05 00:00:00issue
19eissn
0021-9193issn
1098-5530pii
JB.00211-17journal_volume
199pub_type
杂志文章abstract::The phs mutation of Escherichia coli has been suggested to affect the Na+/H+ antiport (D. Zilberstein, E. Padan, and S. Schuldiner, FEBS Lett. 168:327-330, 1980). We have recently shown that the mutation affects the rpoA gene and thus affects transcription. The extent of the pleiotropy of the phs mutation was investig...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.164.2.904-910.1985
更新日期:1985-11-01 00:00:00
abstract::Although Salmonella typhimurium prefers neutral-pH environments, it can adapt to survive conditions of severe low-pH stress (pH 3.3). The process, termed the acid tolerance response (ATR), includes two distinct stages. The first stage, called pre-acid shock, is induced at pH 5.8 and involves the production of an induc...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.7.1981-1987.1993
更新日期:1993-04-01 00:00:00
abstract::The enhancer-binding protein NIFA is required for transcriptional activation of nif promoters by the alternative holoenzyme form of RNA polymerase, which contains the sigma factor sigma 54 (sigma N). NIFA hydrolyzes nucleoside triphosphates to catalyze the isomerization of closed promoter complexes to transcriptionall...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.5.1186-1195.1995
更新日期:1995-03-01 00:00:00
abstract::The recent discovery that the protein DksA acts as a coregulator of genes controlled by ppGpp led us to investigate the similarities and differences between the relaxed phenotype of a ppGpp-deficient mutant and the phenotype of a strain lacking DksA. We demonstrate that the absence of DksA and ppGpp has similar effect...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00330-07
更新日期:2007-07-01 00:00:00
abstract::Reticulate bodies of the meningopneumonitis (MP) microorganism were purified from L cells 18 hr after infection by the combination of differential centrifugation in 30% sucrose solution and potassium tartrate density gradient centrifugation. It was ascertained by electron microscopy that purified preparations of retic...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.93.6.2003-2008.1967
更新日期:1967-06-01 00:00:00
abstract::Expression of virulence factors by Bordetella pertussis is altered by environmental signals (antigenic modulation) and is dependent on an activator encoded by a gene called vir. We have used TnphoA (Tn5 IS50L::phoA) gene fusions to define two sets of genes whose expression is either activated (vag loci) or repressed (...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.170.11.5059-5066.1988
更新日期:1988-11-01 00:00:00
abstract::Mutation of the spoVB gene in Bacillus subtilis causes the production of spores containing a defective cortex and unable to acquire heat resistance. The spoVB locus is highly linked to another spo locus, spoIIIF, characterized by a single mutation (I. L. Lamont and J. Mandelstam, J. Gen. Microbiol. 130:1253-1261, 1984...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.24.7942-7949.1991
更新日期:1991-12-01 00:00:00
abstract::The heat shock response in Escherichia coli involves extensive induction of the heat shock proteins, with the concomitant suppression of the synthesis of the non-heat shock proteins. While the induction of the heat shock proteins has been shown to occur primarily at the transcriptional level, the suppression of non-he...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.3.743-748.1992
更新日期:1992-02-01 00:00:00
abstract::Despite the fact that phosphoenolpyruvate carboxylase (PEPC) activity has been measured and in some cases even purified from some Archaea, the gene responsible for this activity has not been elucidated. Using sensitive sequence comparison methods, we detected a highly conserved, uncharacterized archaeal gene family th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.186.22.7754-7762.2004
更新日期:2004-11-01 00:00:00
abstract::The predominant mode of growth of bacteria in the environment is within sessile, matrix-enclosed communities known as biofilms. Biofilms often complicate chronic and difficult-to-treat infections by protecting bacteria from the immune system, decreasing antibiotic efficacy, and dispersing planktonic cells to distant b...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.1.290-301.2002
更新日期:2002-01-01 00:00:00
abstract::The effect of adding hemin to anaerobically grown cells of a strain of Staphylococcus epidermidis, which was heme-deficient due to anaerobic growth, has been examined. Cells grown anaerobically in media containing hemin exhibited a marked increase in several oxidative activities as compared with cells grown anaerobica...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.93.1.278-285.1967
更新日期:1967-01-01 00:00:00
abstract::Temperature-sensitive nalA mutants of Escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (DNA) gyrase. Extracts of one such mutant (nalA43) had thermosensitive DNA gyrase subunit A activity but normal gyrase subunit B activity, proving definitively that nalA is the stru...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.140.2.424-435.1979
更新日期:1979-11-01 00:00:00
abstract::Pseudomonas aeruginosa isolates from chronic lung infections often overproduce alginate, giving rise to the mucoid phenotype. Isolation of mucoid strains from chronic lung infections correlates with a poor patient outcome. The most common mutation that causes the mucoid phenotype is called mucA22 and results in a trun...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00445-20
更新日期:2020-09-23 00:00:00
abstract::McFadden, B. A. (Washington State University, Pullman), and H. R. Homann. Characteristics and intermediates of short-term C(14)O(2) incorporation during ribose oxidation by Hydrogenomonas facilis. J. Bacteriol. 89:839-847. 1965.-Ribose-grown cells of Hydrogenomonas facilis, which had been suspended in growth medium an...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.89.3.839-847.1965
更新日期:1965-03-01 00:00:00
abstract::The capsular polysaccharide is a critical virulence factor for group B streptococci associated with human infections, yet little is known about capsule biosynthesis. We detected CMP-Neu5Ac synthetase, the enzyme which activates N-acetylneuraminic acid (Neu5Ac, or sialic acid) for transfer to the nascent capsular polys...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.23.7372-7374.1994
更新日期:1994-12-01 00:00:00
abstract::Cell size at bud initiation shows the same relationship to growth rate in wild-type and petite yeast cells. The nutrient-modulated size control is related to growth rate rather than a change from fermentative to oxidative metabolism. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.151.2.1051-1052.1982
更新日期:1982-08-01 00:00:00
abstract::The hook-basal body complex of Salmonella typhimurium, a major component of its flagellar apparatus, was subjected to detailed analysis by electron microscopy and gel electrophoresis. The study was facilitated by the development of an improved protocol for isolation of the complexes in high yield and purity. Nine prot...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.161.3.836-849.1985
更新日期:1985-03-01 00:00:00
abstract::top mutations (formerly supX) eliminate DNA topoisomerase I activity and suppress the leu-500 promoter mutation in Salmonella typhimurium (K. M. Overbye, S. K. Basu, and P. Margolin, Cold Spring Harbor Symp. Quant. Biol. 47:785-791, 1983). Sublethal doses of coumermycin which reduce intracellular levels of supercoilin...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.164.2.947-949.1985
更新日期:1985-11-01 00:00:00
abstract::Hall, Herbert E. (Robert A. Taft Sanitary Engineering Center, Cincinnati, Ohio), Robert Angelotti, Keith H. Lewis, and Milton J. Foter. Characteristics of Clostridium perfringens strains associated with food and food-borne disease. J. Bacteriol. 85:1094-1103. 1963.-A total of 83 strains of Clostridium perfringens-30 f...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.85.5.1094-1103.1963
更新日期:1963-05-01 00:00:00
abstract::We previously described a cell surface anionic polysaccharide (APS) in Porphyromonas gingivalis that is required for cell integrity and serum resistance. APS is a phosphorylated branched mannan that shares a common epitope with posttranslational additions to some of the Arg-gingipains. This study aimed to determine th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01868-07
更新日期:2008-04-01 00:00:00
abstract::At early stages of sporulation, the spoIIA locus is transcribed as a tricistronic (1.7-kb) operon, coding for sigma F and for two proteins that modulate the activity of sigma F. The locus is transcribed as a longer (2.9-kb) transcript at the late stages of sporulation. We show here that the longer transcript contains ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.15.4885-4892.1992
更新日期:1992-08-01 00:00:00
abstract::The effects of temperature and attractants on chemotaxis in psychrotrophic Pseudomonas fluorescens were examined using the Adler capillary assay technique. Several organic acids, amino acids, and uronic acids were shown to be attractants, whereas glucose and its oxidation products, gluconate and 2-ketogluconate, elici...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.143.1.338-342.1980
更新日期:1980-07-01 00:00:00
abstract::There are two closely related hik31 operons involved in signal transduction on the chromosome and the pSYSX plasmid in the cyanobacterium Synechocystis sp. strain PCC 6803. We studied the growth, cell morphology, and gene expression in operon and hik mutants for both copies, under different growth conditions, to exami...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.06207-11
更新日期:2012-01-01 00:00:00
abstract::Membrane vesicles containing internal alcohol dehydrogenase and nicotinamide adenine dinucleotide (NAD) were prepared from Escherichia coli ML308-225. Upon the addition of ethanol, these vesicles respired and transported several amino acids. Transport rates driven by internally generated reduced NAD (NADH) were about ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.120.2.861-865.1974
更新日期:1974-11-01 00:00:00
abstract::The position of the termination codon in lacZX90 was determined by isolation of a lac+ revertant. Lysine was found to replace tyrosine at position 1,012 of beta-galactosidase, indicating that X90 protein lacked the carboxyl-terminal 10 residues. A heat- and urea-sensitive hybrid enzyme was formed in vivo when supC, wh...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.147.2.694-697.1981
更新日期:1981-08-01 00:00:00
abstract::We report here the identification of a new lipoprotein, NlpI, in Escherichia coli K-12. The NlpI structural gene (nlpI) is located between the genes pnp (polynucleotide phosphorylase) and deaD (RNA helicase) at 71 min on the E. coli chromosome. The nlpI gene encodes a putative polypeptide of approximately 34 kDa, and ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.14.4318-4325.1999
更新日期:1999-07-01 00:00:00
abstract::Streptococcus pneumoniae is the causative agent of multiple diseases, including otitis media, pneumonia, bacteremia, and meningitis. Pneumolysin (Ply), a member of the cholesterol-dependent cytolytic pore-forming toxins, is produced by virtually all clinical isolates of S. pneumoniae, and strains in which the Ply gene...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01489-08
更新日期:2009-04-01 00:00:00
abstract::phiYeO3-12 is a T3-related lytic bacteriophage of Yersinia enterocolitica serotype O:3. The nucleotide sequence of the 39,600-bp linear double-stranded DNA (dsDNA) genome was determined. The phage genome has direct terminal repeats of 232 bp, a GC content of 50.6%, and 54 putative genes, which are all transcribed from...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.6.1928-1937.2001
更新日期:2001-03-01 00:00:00
abstract::Structural analogs of S-adenosylhomocysteine were tested in vitro for inhibition of the yeast S-adenosylmethionine:delta 24-sterol-C-methyltransferase enzyme. A wide inhibitory range by these compounds was observed, suggesting which structural features of the parent compound are important for binding to the enzyme. No...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.145.1.106-112.1981
更新日期:1981-01-01 00:00:00
abstract::tolC mutants, which are resistant to colicin E1 and also highly sensitive to detergents and dyes, were shown to lack the OmpF outer membrane protein. There was little effect on transcription as judged by the use of an ompF-lac operon fusion strain, and the tolC effect was probably due to a post-transcriptional effect....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.150.3.1016-1023.1982
更新日期:1982-06-01 00:00:00