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Tao L,
Rouvière PE,
Cheng Q,
( 2006 ) A carotenoid synthesis gene cluster from a non-marine Brevundimonas that synthesizes hydroxylated astaxanthin. PMID : 16781830 : DOI : 10.1016/j.gene.2006.04.017 Abstract >>
A Brevundimonas vesicularis strain DC263 isolated from surface soil was shown to produce hydroxylated astaxanthin. A carotenoid synthesis gene cluster containing ten genes was cloned from strain DC263, among which eight genes were involved in carotenoid synthesis. In addition to the crtW gene encoding the 4,4'-beta-ionone ring ketolase and the crtZ gene encoding the 3,3'-beta-ionone ring hydroxylase that were responsible for astaxanthin synthesis, the cluster also contained a novel gene crtG identified recently encoding the 2,2'-beta-ionone ring hydroxylase that further hydroxylate astaxanthin. The individual genes in the DC263 cluster showed the highest sequence similarities to the corresponding genes reported in Brevundimonas sp. strain SD212, a marine isolate that also produced hydroxylated astaxanthin. The genetic organization of the carotenoid synthesis gene clusters in the two Brevundimonas strains was identical. It is likely that the two Brevundimonas strains were evolved from the same ancestor and adapted later to growth in different environments. Expression of the crtW and crtZ from DC263 in a beta-carotene-accumulating E. coli produced astaxanthin as the predominant carotenoid. The crtG from DC263 and the crtG from another Brevundimonas aurantiaca strain were expressed in E. coli producing different carotenoid substrates. Both CrtG showed low activity on beta-carotene and high activity on zeaxanthin. The main difference was that the CrtG from B. aurantiaca worked well on canthaxanthin or astaxanthin, but the CrtG from DC263 did not work on either of the ketocarotenoids.
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Hill JE,
Penny SL,
Crowell KG,
Goh SH,
Hemmingsen SM,
( 2004 ) cpnDB: a chaperonin sequence database. PMID : 15289485 : DOI : 10.1101/gr.2649204 PMC : PMC509277 Abstract >>
Type I chaperonins are molecular chaperones present in virtually all bacteria, some archaea and the plastids and mitochondria of eukaryotes. Sequences of cpn60 genes, encoding 60-kDa chaperonin protein subunits (CPN60, also known as GroEL or HSP60), are useful for phylogenetic studies and as targets for detection and identification of organisms. Conveniently, a 549-567-bp segment of the cpn60 coding region can be amplified with universal PCR primers. Here, we introduce cpnDB, a curated collection of cpn60 sequence data collected from public databases or generated by a network of collaborators exploiting the cpn60 target in clinical, phylogenetic, and microbial ecology studies. The growing database currently contains approximately 2000 records covering over 240 genera of bacteria, eukaryotes, and archaea. The database also contains over 60 sequences for the archaeal Type II chaperonin (thermosome, a homolog of eukaryotic cytoplasmic chaperonin) from 19 archaeal genera. As the largest curated collection of sequences available for a protein-encoding gene, cpnDB provides a resource for researchers interested in exploiting the power of cpn60 as a diagnostic or as a target for phylogenetic or microbial ecology studies, as well as those interested in broader subjects such as lateral gene transfer and codon usage. We built cpnDB from open source tools and it is available at http://cpndb.cbr.nrc.ca.
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Tayeb LA,
Lefevre M,
Passet V,
Diancourt L,
Brisse S,
Grimont PA,
( 2008 ) Comparative phylogenies of Burkholderia, Ralstonia, Comamonas, Brevundimonas and related organisms derived from rpoB, gyrB and rrs gene sequences. PMID : 18280706 : DOI : 10.1016/j.resmic.2007.12.005 Abstract >>
Phylogenetic analysis of strains from Burkholderia, Ralstonia, Cupriavidus, Comamonas, Delftia, Acidovorax, Brevundimonas, Herbaspirillum huttiense and "Pseudomonas butanovora" was performed based on the protein-coding genes rpoB and gyrB and on the 16S rRNA-coding gene rrs. Overall, the phylogenies deduced from the three genes were concordant among themselves and with current taxonomy. However, a few differences among individual gene phylogenies were noted. For example, the separation of Cupriavidus from Ralstonia was not supported in the rpoB tree, as Ralstonia was nested within Cupriavidus. Similarly, the separation of Delftia from Comamonas was not supported in the gyrB tree. Based on rrs and rpoB, the genus Burkholderia contained four groups: (i) the B. cepacia complex, (ii) the B. pseudomallei-B. thailandensis group, (iii) a 6-species group including B. caledonica and B. glathei and (iv) the B. plantarii-B. glumae-B. gladioli group. However, B. caribensis and B. glathei stood as a fifth group based on gyrB. It appears that a phylogeny cannot be reliably based on a single gene. Using rpoB and gyrB, better separation of closely related species was obtained compared to rrs, indicating the potential of these two genes for identification and species definition. Nevertheless, intraspecific sequence diversity will need to be determined to fully establish the value of these genes for strain identification.
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( 1997 ) Structural studies of malate dehydrogenases (MDHs): MDHs in Brevundimonas species are the first reported MDHs in Proteobacteria which resemble lactate dehydrogenases in primary structure. PMID : 9190829 : DOI : 10.1128/jb.179.12.4066-4070.1997 PMC : PMC179222 Abstract >>
The N-terminal sequences of malate dehydrogenases from 10 bacterial strains, representing seven genera of Proteobacteria, were determined. Of these, the enzyme sequences of species classified in the genus Brevundimonas clearly resembled those malate dehydrogenases with greatest similarity to lactate dehydrogenases. Additional evidence from subunit molecular weights, peptide mapping, and enzyme mobilities suggested that malate dehydrogenases from species of the genus Brevundimonas were structurally distinct from others in the study.
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Ochi K,
( 1995 ) Comparative ribosomal protein sequence analyses of a phylogenetically defined genus, Pseudomonas, and its relatives. PMID : 7727274 : DOI : 10.1099/00207713-45-2-268 Abstract >>
I analyzed various families of ribosomal proteins obtained from selected species belonging to the genus Pseudomonas sensu stricto and allied organisms which were previously classified in the genus Pseudomonas. Partial amino acid sequencing of L30 preparations revealed that the strains which I examined could be divided into three clusters. The first cluster, which was assigned to the genus Pseudomonas sensu stricto, included Pseudomonas aeruginosa, Pseudomonas putida, Pseudomonas mendocina, and Pseudomonas fluorescens. The second cluster included Burkholderia pickettii and Burkholderia plantarii. The third cluster, which was a deeply branching cluster in the stem of gram-negative bacteria, included Brevundimonas diminuta and Brevundimonas vesicularis. Despite the different levels of conservation of the N-terminal sequences of ribosomal protein families (the highest level of similarity was 74% for L27 proteins and the lowest level of similarity was 42% for L30 proteins), similar phylogenetic trees were constructed by using data obtained from sequence analyses of various ribosomal protein families, including the S20, S21, L27, L29, L31, L32, and L33 protein families. Thus, I demonstrated the efficacy of ribosomal protein analysis in bacterial taxonomy.
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