Abstract:
:The biosynthesis of the thaxtomin cyclic dipeptide phytotoxins proceeds nonribosomally via the thiotemplate mechanism. Acyladenylation, thioesterification, N-methylation, and cyclization of two amino acid substrates are catalyzed by the txtAB-encoded thaxtomin synthetase. Nucleotide sequence analysis of the region 3' of txtAB in Streptomyces acidiscabies 84.104 identified an open reading frame (ORF) encoding a homolog of the P450 monooxygenase gene family. It was proposed that thaxtomin A phenylalanyl hydroxylation was catalyzed by the monooxygenase homolog. The ORF was mutated in S. acidiscabies 84.104 by using an integrative gene disruption construct, and culture filtrate extracts of the mutant were assayed for the presence of dehydroxy derivatives of thaxtomin A. Reversed-phase high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry indicated that the major component in culture filtrate extracts of the mutant was less polar and smaller than thaxtomin A. Comparisons of electrospray mass spectra as well as (1)H- and (13)C-nuclear magnetic resonance spectra of the purified compound with those previously reported for thaxtomins confirmed the structure of the compound as 12,15-N-dimethylcyclo-(L-4-nitrotryptophyl-L-phenylalanyl), the didehydroxy analog of thaxtomin A. The ORF, designated txtC, was cloned and the recombinant six-His-tagged fusion protein produced in Escherichia coli and purified from cell extracts. TxtC produced in E. coli exhibited spectral properties similar to those of cytochrome P450-type hemoproteins that have undergone conversion to the catalytically inactive P420 form. Based on these properties and the high similarity of TxtC to other well-characterized P450 enzymes, we conclude that txtC encodes a cytochrome P450-type monooxygenase required for postcyclization hydroxylation of the cyclic dipeptide.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Healy FG,Krasnoff SB,Wach M,Gibson DM,Loria Rdoi
10.1128/jb.184.7.2019-2029.2002keywords:
subject
Has Abstractpub_date
2002-04-01 00:00:00pages
2019-29issue
7eissn
0021-9193issn
1098-5530journal_volume
184pub_type
杂志文章abstract::The enzymes LinB(UT) and LinB(MI) (LinB from Sphingobium japonicum UT26 and Sphingobium sp. MI1205, respectively) catalyze the hydrolytic dechlorination of β-hexachlorocyclohexane (β-HCH) and yield different products, 2,3,4,5,6-pentachlorocyclohexanol (PCHL) and 2,3,5,6-tetrachlorocyclohexane-1,4-diol (TCDL), respecti...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.02020-12
更新日期:2013-06-01 00:00:00
abstract::The galP1 promoter is responsible for galactose-dependent, glucose-sensitive transcription of the galactose utilization operon of Streptomyces coelicolor and Streptomyces lividans. We describe the characterization of mutations that were positioned directly upstream of the apparent transcription start site of galP1 and...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.5.1213-1220.1993
更新日期:1993-03-01 00:00:00
abstract::Flac mutants have been isolated in Escherichia coli K-12 which carry dominant mutations resulting in insensitivity to transfer inhibition by the Fin(+) I-like plasmid R62. These mutants were still sensitive to transfer inhibition by the fin(+) F-like plasmid R100 and, conversely, FlactraO(-) and traP(-) mutants, which...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.120.1.101-105.1974
更新日期:1974-10-01 00:00:00
abstract::Spontaneous mutants that were resistant to zinc were isolated from Alcaligenes eutrophus CH34 containing either the native plasmid pMOL28 or a derivative derepressed for its self-transfer, pMOL50. With the cured plasmid-free derivative of CH34, strain AE104, such mutants were not detected. The mutations, which were sh...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.3.779-784.1993
更新日期:1993-02-01 00:00:00
abstract::Outer membrane alterations were characterized in spontaneous mutants of the Erwinia chrysanthemi 3937jRH, which were selected for resistance to bacteriophage phi EC2. All but one of the mutants analyzed were affected in their lipopolysaccharide (LPS) structure, lacking the entire heterogeneous region of apparent high ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.9.4011-4017.1987
更新日期:1987-09-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01111-12
更新日期:2012-10-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00795-17
更新日期:2018-03-26 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.21.6970-6981.1993
更新日期:1993-11-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.129.3.1476-1486.1977
更新日期:1977-03-01 00:00:00
abstract::Two replicons were isolated independently from different IncHI1 plasmids. One was isolated from R27, and a second was isolated from pIP522. We demonstrate, by DNA-DNA hybridization experiments, that these maintenance regions are different and that they are specific to, and carried by, all IncHI1 plasmids tested. In vi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.23.7697-7701.1993
更新日期:1993-12-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.97.2.734-742.1969
更新日期:1969-02-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.116.3.1479-1481.1973
更新日期:1973-12-01 00:00:00
abstract::The inner or cytoplasmic membrane fraction of the cell envelope of Escherichia coli was isolated by isopycnic centrifugation on sucrose gradients. The membrane proteins were analyzed by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels (8.5%), and up to 56 bands were resolved. Different preparations gave v...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.117.3.947-953.1974
更新日期:1974-03-01 00:00:00
abstract::The interaction of Streptococcus pyogenes (group A streptococcus [GAS]) with its human host requires several surface proteins. In this study, we isolated mutations in a gene required for the surface localization of protein F by transposon mutagenesis of the M6 strain JRS4. This gene (srtA) encodes a protein homologous...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.8.2181-2191.2002
更新日期:2002-04-01 00:00:00
abstract::Screening of derivatives of Rhizobium etli KIM5s randomly mutagenized with mTn5SSgusA30 resulted in the identification of strain KIM-G1. Its rough colony appearance, flocculation in liquid culture, and Ndv(-) Fix(-) phenotype were indicative of a lipopolysaccharide (LPS) defect. Electrophoretic analysis of cell-associ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.18.5606-5614.1999
更新日期:1999-09-01 00:00:00
abstract::Levy, Stuart B. (Institut du Radium, Paris, France). Isologous interference with ultraviolet and X-ray irradiated bacteriophage T(2). J. Bacteriol. 87:1330-1338. 1964.-Qualitative and quantitative analysis of the interference capacity of an irradiated T(2) bacteriophage was made with ultraviolet and X-ray irradiation....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.87.6.1330-1338.1964
更新日期:1964-06-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.12.3894-3900.1991
更新日期:1991-06-01 00:00:00
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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::Campbell, J. J. R. (The University of British Columbia, Vancouver, B.C., Canada), Loretta A. Hogg, and G. A. Strasdine. Enzyme distribution in Pseudomonas aeruginosa. J. Bacteriol. 83:1155-1160. 1962.-Previous studies on the distribution of enzymes in bacteria have indicated that, although individual enzymes were pred...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.83.5.1155-1160.1962
更新日期:1962-05-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.159.2.618-623.1984
更新日期:1984-08-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.12.3601-3607.1996
更新日期:1996-06-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.20.6479-6487.1992
更新日期:1992-10-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.8.2920-2925.2005
更新日期:2005-04-01 00:00:00
abstract::The sequencing of the EcoRI-HindIII fragment complementing mutations in the structural genes of the L-rhamnose regulon of Escherichia coli has permitted identification of the open reading frames corresponding to rhaB, rhaA, and rhaD. The deduced amino acid sequences gave a 425-amino-acid polypeptide corresponding to r...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.17.5585-5594.1993
更新日期:1993-09-01 00:00:00
abstract::Hirota, Yukinori (University of Osaka, Osaka, Japan), Toshio Fujii, and Yukinobu Nishimura. Loss and repair of conjugal fertility and infectivity of the resistance factor and sex factor in Escherichia coli. J. Bacteriol. 91:1298-1304. 1966.-The drug-resistance factor, R, and the sex factor, F, have homologous traits, ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.91.3.1298-1304.1966
更新日期:1966-03-01 00:00:00
abstract::The global regulator CsrA (carbon storage regulator) is an RNA binding protein that coordinates central carbon metabolism, activates flagellum biosynthesis and motility, and represses biofilm formation in Escherichia coli. CsrA activity is antagonized by the untranslated RNA CsrB, to which it binds and forms a globula...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.18.5130-5140.2002
更新日期:2002-09-01 00:00:00
abstract::The cell envelope of gram-negative bacteria is responsible for many important biological functions: it plays a structural role, it accommodates the selective transfer of material across the cell wall, it undergoes changes made necessary by growth and division, and it transfers information about the environment into th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00132-08
更新日期:2008-06-01 00:00:00
abstract::ShdA is a large outer membrane protein of the autotransporter family whose passenger domain binds the extracellular matrix proteins fibronectin and collagen I, possibly by mimicking the host ligand heparin. The ShdA passenger domain consists of approximately 1,500 amino acid residues that can be divided into two regio...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.186.15.4931-4939.2004
更新日期:2004-08-01 00:00:00
abstract::Cells of Bacillus thuringiensis containing refractile spores autolyzed readily when suspended in buffer. The autolysate contained enzymes which lysed vegetative cell walls of the organism. Three enzymes were isolated from the autolysate, and each was purified approximately 30-fold. One enzyme, most active near pH 4.0,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.96.3.629-638.1968
更新日期:1968-09-01 00:00:00
abstract::The spoIIG promoter is used by RNA polymerase containing sigma A (E sigma A), the primary form of RNA polymerase found in vegetative cells in Bacillus subtilis. However, the spoIIG promoter is active only after the onset of sporulation. Activation of the spoIIG promoter requires the product of the spo0A gene (Spo0A). ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.5.1448-1453.1992
更新日期:1992-03-01 00:00:00