scholarly journals Neisseria conserved hypothetical protein DMP12 is a DNA mimic that binds to histone-like HU protein

2013 ◽  
Vol 41 (9) ◽  
pp. 5127-5138 ◽  
Author(s):  
Hao-Ching Wang ◽  
Mao-Lun Wu ◽  
Tzu-Ping Ko ◽  
Andrew H.-J. Wang
2012 ◽  
Vol 78 (15) ◽  
pp. 5238-5246 ◽  
Author(s):  
Dongfei Han ◽  
Ji-Young Ryu ◽  
Robert A. Kanaly ◽  
Hor-Gil Hur

ABSTRACTA plasmid, pTA163, inEscherichia colicontained an approximately 34-kb gene fragment fromPseudomonas putidaJYR-1 that included the genes responsible for the metabolism oftrans-anethole to protocatechuic acid. Three Tn5-disrupted open reading frame 10 (ORF 10) mutants of plasmid pTA163 lost their abilities to catalyzetrans-anethole. Heterologously expressed ORF 10 (1,047 nucleotides [nt]) under a T7 promoter inE. colicatalyzed oxidative cleavage of a propenyl group oftrans-anethole to an aldehyde group, resulting in the production ofpara-anisaldehyde, and this gene was designatedtao(trans-anetholeoxygenase). The deduced amino acid sequence of TAO had the highest identity (34%) to a hypothetical protein ofAgrobacterium vitisS4 and likely contained a flavin-binding site. Preferred incorporation of an oxygen molecule from water intop-anisaldehyde using18O-labeling experiments indicated stereo preference of TAO for hydrolysis of the epoxide group. Interestingly, unlike the narrow substrate range of isoeugenol monooxygenase fromPseudomonas putidaIE27 andPseudomonas nitroreducensJin1, TAO fromP. putidaJYR-1 catalyzed isoeugenol,O-methyl isoeugenol, and isosafrole, all of which contain the 2-propenyl functional group on the aromatic ring structure. Addition of NAD(P)H to the ultrafiltered cell extracts ofE. coli(pTA163) increased the activity of TAO. Due to the relaxed substrate range of TAO, it may be utilized for the production of various fragrance compounds from plant phenylpropanoids in the future.


2002 ◽  
Vol 46 (6) ◽  
pp. 1823-1830 ◽  
Author(s):  
Jean-Denis Docquier ◽  
Fabrizio Pantanella ◽  
Francesco Giuliani ◽  
Maria Cristina Thaller ◽  
Gianfranco Amicosante ◽  
...  

ABSTRACT The sequenced chromosome of Caulobacter crescentus CB15 encodes a hypothetical protein that exhibits significant similarity (30 to 35% identical residues) to metallo-β-lactamases of subclass B3. An allelic variant of this gene (divergent by 3% of its nucleotides) was cloned in Escherichia coli from C. crescentus type strain DSM4727. Expression studies confirmed the metallo-β-lactamase activity of its product, CAU-1. The enzyme produced in E. coli was purified by two ion-exchange chromatography steps. CAU-1 contains a 29-kDa polypeptide with an alkaline isoelectric pH (>9), and unlike the L1 enzyme of Stenotrophomonas maltophilia, the native form is monomeric. Kinetic analysis revealed a preferential activity toward penicillins, carbapenems, and narrow-spectrum cephalosporins, while oxyimino cephalosporins were poorly or not hydrolyzed. Affinities for the various β-lactams were poor overall (Km values were always >100 μM and often >400 μM). The interaction with divalent ion chelators appeared to occur by a mechanism similar to that prevailing in other members of subclass B3. In C. crescentus, the CAU-1 enzyme is produced independently of β-lactam exposure and, interestingly, the bla CAU determinant is bracketed by three other genes, including two genes encoding enzymes involved in methionine biosynthesis and a gene encoding a putative transcriptional regulator, in an operon-like structure. The CAU-1 enzyme is the first example of a metallo-β-lactamase in a member of the α subdivision of the class Proteobacteria.


2000 ◽  
Vol 302 (1) ◽  
pp. 189-203 ◽  
Author(s):  
John R Cort ◽  
Adelinda Yee ◽  
Aled M Edwards ◽  
Cheryl H Arrowsmith ◽  
Michael A Kennedy

2009 ◽  
Vol 2009 ◽  
pp. 1-10 ◽  
Author(s):  
Daniela Lepka ◽  
Tobias Kerrinnes ◽  
Evelyn Skiebe ◽  
Birgitt Hahn ◽  
Angelika Fruth ◽  
...  

We report the nucleotide sequence of two novel cryptic plasmids (4357 and 14 662 base pairs) carried by aYersinia enterocoliticabiotype 1A strain isolated from pork. As distinguished from most biotype 1A strains, this isolate, designated 07-04449, exhibited adherence to eukaryotic cells. The smaller plasmid pYe4449-1 carries five attributable open reading frames (ORFs) encoding the first CcdA/CcdB-like antitoxin/toxin system described for aYersiniaplasmid, a RepA-like replication initiation protein, and mobilizing factors MobA and MobC. The deduced amino acid sequences showed highest similarity to proteins described inSalmonella(CcdA/B),Klebsiella(RepA), andPlesiomonas(MobA/C) indicating genomic fluidity among members of theEnterobacteriaceae. One additional ORF with unknown function, termed ORF5, was identified with an ancestry distinct from the rest of the plasmid. While the C+G content of ORF5 is 38.3%, the rest of pYe4449-1 shows a C+G content of 55.7%. The C+G content of the larger plasmid pYe4449-2 (54.9%) was similar to that of pYe4449-1 (53.7%) and differed from that of theY. enterocoliticagenome (47.3%). Of the 14 ORFs identified on pYe4449-2, only six ORFs showed significant similarity to database entries. For three of these ORFs likely functions could be ascribed: a TnpR-like resolvase and a phage replication protein, localized each on a low C+G island, and DNA primase TraC. Two ORFs of pYe4449-2, ORF3 and ORF7, seem to encode secretable proteins. Epitope-tagging of ORF3 revealed protein expression at4°Cbut not at or above27°Csuggesting adaptation to a habitat outside swine. The hypothetical protein encoded by ORF7 is the member of a novel repeat protein family sharing theDxxGN(x)nDxxGNmotif. Our findings illustrate the exceptional gene pool diversity within the speciesY. enterocoliticadriven by horizontal gene transfer events.


2021 ◽  
Vol 8 (1) ◽  
pp. 6-10
Author(s):  
Hani Moubasher ◽  
Salwa S Wahsh ◽  
Nabil Abo El-Kassem ◽  
Refaat Ali

Sequancing of pullulanase from the fungus Aureobasidium pullulans isolated from Egypt soil; Genomic DNA of pullulanase was determined for the first time using PCR, according to Baser program, Pullulanase nucleotide collection from Aureobasidium pullulans was blasted which showed similarity using NCBI significant alignment with Aureobasidium namibiae CBS 147.97 hypothetical protein partial mRNA and 46 % with Aureobasidium pullulans JQ624241 and AF470619; Identified sequenced fragment was 2051 bp. and G+C content is 50.5% with molecular mass 63 KDa.


2001 ◽  
Vol 183 (7) ◽  
pp. 2172-2177 ◽  
Author(s):  
Jonathan G. Krum ◽  
Scott A. Ensign

ABSTRACT The bacterial metabolism of propylene proceeds by epoxidation to epoxypropane followed by a sequence of three reactions resulting in epoxide ring opening and carboxylation to form acetoacetate. Coenzyme M (2-mercaptoethanesulfonic acid) (CoM) plays a central role in epoxide carboxylation by serving as the nucleophile for epoxide ring opening and the carrier of the C3 unit that is ultimately carboxylated to acetoacetate, releasing CoM. In the present work, a 320-kb linear megaplasmid has been identified in the gram-negative bacterium Xanthobacter strain Py2, which contains the genes encoding the key enzymes of propylene oxidation and epoxide carboxylation. Repeated subculturing of Xanthobacter strain Py2 under nonselective conditions, i.e., with glucose or acetate as the carbon source in the absence of propylene, resulted in the loss of the propylene-positive phenotype. The propylene-negative phenotype correlated with the loss of the 320-kb linear megaplasmid, loss of induction and expression of alkene monooxgenase and epoxide carboxylation enzyme activities, and the loss of CoM biosynthetic capability. Sequence analysis of a hypothetical protein (XecG), encoded by a gene located downstream of the genes for the four enzymes of epoxide carboxylation, revealed a high degree of sequence identity with proteins of as-yet unassigned functions in the methanogenic archaeaMethanobacterium thermoautotrophicum andMethanococcus jannaschii and in Bacillus subtilis. The M. jannaschii homolog of XecG, MJ0255, is located next to a gene, MJ0256, that has been shown to encode a key enzyme of CoM biosynthesis (M. Graupner, H. Xu, and R. H. White, J. Bacteriol. 182: 4862–4867, 2000). We propose that the propylene-positive phenotype of Xanthobacter strain Py2 is dependent on the selective maintenance of a linear megaplasmid containing the genes for the key enzymes of alkene oxidation, epoxide carboxylation, and CoM biosynthesis.


2014 ◽  
Vol 136 (6) ◽  
pp. 2204-2207 ◽  
Author(s):  
Arvind Kannan ◽  
Carlo Camilloni ◽  
Aleksandr B. Sahakyan ◽  
Andrea Cavalli ◽  
Michele Vendruscolo

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