Abstract:
:Phosphate acetyltransferase (PTA) and acetate kinase (AK) of the hyperthermophilic eubacterium Thermotoga maritima have been purified 1,500- and 250-fold, respectively, to apparent homogeneity. PTA had an apparent molecular mass of 170 kDa and was composed of one subunit with a molecular mass of 34 kDa, suggesting a homotetramer (alpha4) structure. The N-terminal amino acid sequence showed significant identity to that of phosphate butyryltransferases from Clostridium acetobutylicum rather than to those of known phosphate acetyltransferases. The kinetic constants of the reversible enzyme reaction (acetyl-CoA + Pi -->/<-- acetyl phosphate + CoA) were determined at the pH optimum of pH 6.5. The apparent Km values for acetyl-CoA, Pi, acetyl phosphate, and coenzyme A (CoA) were 23, 110, 24, and 30 microM, respectively; the apparent Vmax values (at 55 degrees C) were 260 U/mg (acetyl phosphate formation) and 570 U/mg (acetyl-CoA formation). In addition to acetyl-CoA (100%), the enzyme accepted propionyl-CoA (60%) and butyryl-CoA (30%). The enzyme had a temperature optimum at 90 degrees C and was not inactivated by heat upon incubation at 80 degrees C for more than 2 h. AK had an apparent molecular mass of 90 kDa and consisted of one 44-kDa subunit, indicating a homodimer (alpha2) structure. The N-terminal amino acid sequence showed significant similarity to those of all known acetate kinases from eubacteria as well that of the archaeon Methanosarcina thermophila. The kinetic constants of the reversible enzyme reaction (acetyl phosphate + ADP -->/<-- acetate + ATP) were determined at the pH optimum of pH 7.0. The apparent Km values for acetyl phosphate, ADP, acetate, and ATP were 0.44, 3, 40, and 0.7 mM, respectively; the apparent Vmax values (at 50 degrees C) were 2,600 U/mg (acetate formation) and 1,800 U/mg (acetyl phosphate formation). AK phosphorylated propionate (54%) in addition to acetate (100%) and used GTP (100%), ITP (163%), UTP (56%), and CTP (21%) as phosphoryl donors in addition to ATP (100%). Divalent cations were required for activity, with Mn2+ and Mg2+ being most effective. The enzyme had a temperature optimum at 90 degrees C and was stabilized against heat inactivation by salts. In the presence of (NH4)2SO4 (1 M), which was most effective, the enzyme did not lose activity upon incubation at 100 degrees C for 3 h. The temperature optimum at 90 degrees C and the high thermostability of both PTA and AK are in accordance with their physiological function under hyperthermophilic conditions.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Bock AK,Glasemacher J,Schmidt R,Schönheit Pdoi
10.1128/JB.181.6.1861-1867.1999keywords:
subject
Has Abstractpub_date
1999-03-01 00:00:00pages
1861-7issue
6eissn
0021-9193issn
1098-5530journal_volume
181pub_type
杂志文章abstract::The gene encoding an extracellular isomalto-dextranase, designated imd, was isolated from the chromosomal DNA of Arthrobacter globiformis T6 and cloned and expressed in Escherichia coli. A single open reading frame consisting of 1,926 base pairs that encoded a polypeptide composed of a signal peptide of 39 amino acids...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.24.7730-7734.1994
更新日期:1994-12-01 00:00:00
abstract::Expression of the pneumococcal type 1 pilus is bistable and positively regulated by the transcription factor RlrA. RlrA is also known to positively control its own expression. Here we present evidence that bistable expression of the type 1 pilus is mediated by the positive-feedback loop controlling rlrA expression. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.06078-11
更新日期:2012-03-01 00:00:00
abstract::Previously we have described a mutant Hfr strain in which incompatibility between the integrated F factor and an autonomous F-prime (F') factor was abolished. The mutation (inc) was located in the integrated F factor. F-prime factors isolated from the mutant Hfr strain have the same incompatibility behavior as those i...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.127.1.348-353.1976
更新日期:1976-07-01 00:00:00
abstract::The Mg-2+-Sarkosyl crystals (M band) procedure was used to study the effect of ribonuclease (RNase) A on the association of Escherichia coli deoxyribonucleic acid (DNA) with membrane. Incubation of gently prepared cell extracts with RNase results in the release of DNA from membrane. This effect appears to result from ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.122.2.592-598.1975
更新日期:1975-05-01 00:00:00
abstract::The regulation of Agrobacterium tumefaciens heat shock genes involves a transcriptional activator (RpoH) and repressor elements (HrcA-CIRCE). Using proteome analysis and mutants in these control elements, we show that the heat shock induction of 32 (out of 56) heat shock proteins is independent of RpoH and HrcA. These...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.6.1772-1778.2002
更新日期:2002-03-01 00:00:00
abstract::The bacterium Photorhabdus luminescens is a symbiont of the entomopathogenic nematode Heterorhabditis bacteriophora. The nematode requires the bacterium for infection of insect larvae and as a substrate for growth and reproduction. The nematodes do not grow and reproduce in insect hosts or on artificial media in the a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.10.3117-3126.2001
更新日期:2001-05-01 00:00:00
abstract::Polyamines are present in high concentrations in archaea, yet little is known about their synthesis, except by extrapolation from bacterial and eucaryal systems. S-Adenosylmethionine (AdoMet) decarboxylase, a pyruvoyl group-containing enzyme that is required for spermidine biosynthesis, has been previously identified ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.23.6667-6672.2000
更新日期:2000-12-01 00:00:00
abstract::The intestinal pathogen Clostridium difficile is known to grow only within the intestines of mammals, yet little is known about how the bacterium subsists in this environment. In the intestine, C. difficile must contend with innate defenses within the host, such as cationic antimicrobial peptides (CAMPs) produced by t...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00166-13
更新日期:2013-06-01 00:00:00
abstract::The Bacillus subtilis anti-TRAP protein regulates the ability of the tryptophan-activated TRAP protein to bind to trp operon leader RNA and promote transcription termination. AT synthesis is regulated both transcriptionally and translationally by uncharged tRNA(Trp). In this study, we examined the roles of AT synthesi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01820-07
更新日期:2008-03-01 00:00:00
abstract::Genetic diversity and relationships in 74 Helicobacter pylori isolates recovered from patients assigned to distinct clinical categories were estimated by examination of allelic variation in six genes encoding metabolic housekeeping enzymes by multilocus enzyme electrophoresis. Seventy-three distinct allele profiles, r...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.13.3934-3938.1996
更新日期:1996-07-01 00:00:00
abstract::We have identified three new Haemophilus influenzae mutations causing cells to exhibit extreme hypercompetence at all stages of growth. The mutations are in murE, which encodes the meso-diaminopimelate-adding enzyme of peptidoglycan synthesis. All are point mutations causing nonconservative amino acid substitutions, t...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.12.3323-3330.2000
更新日期:2000-06-01 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::A procedure was developed for purification of ornithine transcarbamylase (OTCase) to near homogeneity from Bacillus subtilis 168. The purified native enzyme existed as a mixture of dimeric, tetrameric, and hexameric forms, but was converted to the dimer in the presence of 2-mercaptoethanol. The molecular weight of the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.155.2.512-521.1983
更新日期:1983-08-01 00:00:00
abstract::The enzyme pattern of Saccharomyces cerevisiae was followed during batch growth and in continuous culture in a synthetic medium limited for glucose under aerobic conditions. Seven enzymes were measured: succinate-cytochrome c oxidoreductase, malate dehydrogenase, nicotinamide adenine dinucleotide-linked glutamate dehy...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.96.2.479-486.1968
更新日期:1968-08-01 00:00:00
abstract::A strain of Escherichia coli with a mutation in the promoter proximal gene ( uncI ) of the unc operon has been constructed by using a new gene replacement method. The mutation is a deletion of a defined sequence of 196 base pairs. It was constructed by homologous integration and segregation of a ColE1-derived recombin...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.158.3.820-825.1984
更新日期:1984-06-01 00:00:00
abstract::Strains of Escherichia coli lacking all cytoplasmic chemotaxis proteins except CheY swim smoothly under most conditions. However, they tumble when exposed to acetate. Acetate coenzyme A synthetase (EC 6.2.1.1) was thought to be essential for this response. New evidence suggests that the tumbling is mediated instead by...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.10.3236-3239.1993
更新日期:1993-05-01 00:00:00
abstract::The toxR gene of Vibrio cholerae encodes a transcriptional activator required for the expression of the cholera toxin genes (ctxAB) and more than 15 other genes encoding secreted or membrane proteins. The latter group includes virulence genes involved in the biogenesis of the TCP pilus, the accessory colonization fact...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.9.2842-2851.1991
更新日期:1991-05-01 00:00:00
abstract::Salmonella enterica can utilize fructose-asparagine (F-Asn) as a source of carbon and nitrogen. This capability has been attributed to five genes in the fra locus. Previously, we determined that mutations in fraB (deglycase), fraD (kinase), or fraA (transporter) eliminated the ability of Salmonella to grow on F-Asn, w...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00330-17
更新日期:2017-10-17 00:00:00
abstract::Streptococcus faecalis obtains metabolic energy chiefly from the conversion of glucose to lactic acid; the present experiments deal with the mechanism of lactic acid translocation across the cytoplasmic membrane. Efflux of [(14)C]lactate from preloaded cells was accelerated by raising the external pH, and also by the ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.117.3.1141-1148.1974
更新日期:1974-03-01 00:00:00
abstract::The sdiA gene codes for a protein that regulates expression of the ftsQAZ cluster of essential cell division genes of Escherichia coli. SdiA up-regulates the ftsQ2p promoter that initiates transcription into the ftsQAZ cluster. In this paper, we report that expression of sdiA is itself regulated by a factor that is re...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.10.2742-2748.1996
更新日期:1996-05-01 00:00:00
abstract::Chimeric plasmids, which were useful as cloning vehicles in a Streptococcus sanguis (Challis) host vector system, have been constructed. By using three different strategies of restriction endonuclease digestion and ligation, a deoxyribonucleic acid (DNA) fragment bearing an erythromycin resistance determinant was liga...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.143.3.1425-1435.1980
更新日期:1980-09-01 00:00:00
abstract::Specific localization of the lysis (L) protein of bacteriophage MS2 in the cell wall of Escherichia coli was determined by immunoelectron microscopy. After induction of the cloned lysis gene, the cells were plasmolyzed, fixed, and embedded in either Epon or Lowicryl K4M. Polyclonal L-protein-specific antiserum was pur...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.6.3331-3336.1989
更新日期:1989-06-01 00:00:00
abstract::Cytochrome bd oxidase operons from more than 50 species of bacteria contain a short gene encoding a small protein that ranges from ∼30 to 50 amino acids and is predicted to localize to the cell membrane. Although cytochrome bd oxidases have been studied for more than 70 years, little is known about the role of this sm...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00324-13
更新日期:2013-08-01 00:00:00
abstract::The c subunit of Streptococcus mutans ATP synthase (FoF1) is functionally exchangeable with that of Escherichia coli, since E. coli with a hybrid FoF1 is able to grow on minimum succinate medium through oxidative phosphorylation. E. coli F1 bound to the hybrid Fo with the S. mutans c subunit showed N,N'-dicyclohexylca...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00542-13
更新日期:2013-11-01 00:00:00
abstract::Legionella pneumophila is the causative agent of the severe and potentially fatal pneumonia Legionnaires' disease. L. pneumophila is able to replicate within macrophages and protozoa by establishing a replicative compartment in a process that requires the Icm/Dot type IVB secretion system. The signals and regulatory p...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01578-08
更新日期:2009-04-01 00:00:00
abstract::The effects of the free bile acids (FBAs) cholic acid (CA), deoxycholic acid (DCA), and chenodeoxycholic acid on the bioenergetics and growth of lactobacilli and bifidobacteria were investigated. It was found that these FBAs reduced the internal pH levels of these bacteria with rapid and stepwise kinetics and, at cert...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.188.5.1979-1986.2006
更新日期:2006-03-01 00:00:00
abstract::SpoVM is an unusually small (26-residue-long) protein that is produced in the mother cell chamber of the sporangium during the process of sporulation in Bacillus subtilis. We investigated the subcellular localization of SpoVM, which is believed to be an amphipathic alpha-helix, by using a fusion of the sporulation pro...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.4.1391-1398.2003
更新日期:2003-02-01 00:00:00
abstract::It has been clear for over sixty years that the principal method whereby cells replicate and segregate their DNA is semiconservative. It is much less clear why it should be like this rather than, say, conservative. Recently, evidence has accumulated that supports the hypothesis that one of the functions of the cell cy...
journal_title:Journal of bacteriology
pub_type: 杂志文章,评审
doi:10.1128/JB.00119-19
更新日期:2019-05-22 00:00:00
abstract::A number of catalase-deficient mutants of Escherichia coli which exhibit no assayable catalase activity were isolated. The only physiological difference between the catalase mutants and their parents was a 50- to 60-fold greater sensitivity to killing by hydrogen peroxide. For comparison, mutations in the xthA and rec...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.157.2.622-626.1984
更新日期:1984-02-01 00:00:00
abstract::A genetically homogenous bacterial population may contain physiologically distinct subpopulations. In one such case, a minor part of an otherwise antibiotic-sensitive bacterial population maintains a nondividing state even in a growth-supporting environment and is therefore not killed by bactericidal antibiotics. This...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00056-10
更新日期:2010-07-01 00:00:00