PMID(sorted descending)
characterization and application of fusidane antibiotic biosynethsis enzyme 3-ketosteroid-∆(1)-dehydrogenase in steroid transformation.microbial ∆ ( 1 ) -dehydrogenation is one of the most important transformations in the synthesis of steroid hormones. in this study, a 3-ketosteroid-∆(1)-dehydrogenase (kstd(f)) involved in fusidane antibiotic biosynthesis from aspergillus fumigatus cicc 40167 was characterized for use in steroid transformation. kstd(f) encodes a polypeptide consisting of 637 amino acid residues. it shows 51% amino acid identi ...201222234537
the phylogenetic placement of the non-phototrophic gram-positive thermophile thermobaculum terrenum and branching orders within the phylum chloroflexi inferred from gene order comparisons.the phylogenetic position of an anaerobic non-spore-forming thermophile thermobaculum terrenum was investigated on the basis of gene order data from completely sequenced bacterial genomes. gene order data can be an excellent source of phylogenetic information. shared gene arrangements are unlikely to have arisen by chance convergence. they are likely to reflect a common ancestry. t. terrenum was found to share five gene arrangements that are present uniquely in the chloroflexi genomes, indicatin ...201020833875
complete genome sequence of the aerobic co-oxidizing thermophile thermomicrobium order to enrich the phylogenetic diversity represented in the available sequenced bacterial genomes and as part of an "assembling the tree of life" project, we determined the genome sequence of thermomicrobium roseum dsm 5159. t. roseum dsm 5159 is a red-pigmented, rod-shaped, gram-negative extreme thermophile isolated from a hot spring that possesses both an atypical cell wall composition and an unusual cell membrane that is composed entirely of long-chain 1,2-diols. its genome is composed o ...200919148287
long-chain diols: a new class of membrane lipids from a thermophilic bacterium.glycerol-derived membrane lipids are essentially absent in the thermophilic bacterium thermomicrobium roseum. a series of straight chain and internally methyl-branched 1,2-diols of carbon numbers c(18) to c(23) were found to replace glycerolipids in this bacterium. fatty acids were present but were ester-linked to the diols or amide-linked to polar heads groups and not to glycerol. this thermophile has evolved the integration of diols as a novel approach for the construction of its cytoplasmic m ...198617818542
reclassification of sphaerobacter thermophilus from the subclass sphaerobacteridae in the phylum actinobacteria to the class thermomicrobia (emended description) in the phylum chloroflexi (emended description).sphaerobacter thermophilus was originally classified as the deepest branching member of the phylum actinobacteria (high-g+c, gram-positive bacteria) based on 16s rrna gene comparative analysis. however, the analysis lacked suitable outgroups, and additional 16s rrna gene sequences indicate that it is most closely related to thermomicrobium roseum, which it also resembles phenotypically. furthermore, both species are reproducibly affiliated with the phylum chloroflexi (green non-sulfur bacteria), ...200415545432
the highly stable alcohol dehydrogenase of thermomicrobium roseum: purification and molecular alcohol dehydrogenase (adh) was purified to electrophoretic homogeneity from an extremely thermophilic bacterium, thermomicrobium roseum. the native enzyme was found to be a homo-dimer of 43-kda subunits. the pi of the enzyme was determined to be 6.2, while its optimum ph is 10.0. the enzyme oxidized mainly primary aliphatic alcohols and exhibited high substrate specificity towards ethanol, n-propanol and crotyl alcohol. the highest reaction rate was observed when ethanol was used as substrat ...200212031468
the deinococcus-thermus phylum and the effect of rrna composition on phylogenetic tree construction.through comparative analysis of 16s ribosomal rna sequences, it can be shown that two seemingly dissimilar types of eubacteria deinococcus and the ubiquitous hot spring organism thermus are distantly but specifically related to one another. this confirms an earlier report based upon 16s rrna oligonucleotide cataloging studies (hensel et al., 1986). their two lineages form a distinctive grouping within the eubacteria that deserved the taxonomic status of a phylum. the (partial) sequence of t. ...198911542160
the green non-sulfur bacteria: a deep branching in the eubacterial line of descent.ribosomal rna sequence comparisons define a phylogenetic grouping, the green non-sulfur bacteria and relatives (gns), known to contain the genera chloroflexus, herpetosiphon and thermomicrobium--organisms that have little phenotypic similarity. the unit is phylogenetically deep, but entirely distinct from any other eubacterial division (phylum). it is also relatively ancient--branching from the common eubacterial stem earlier than any other group of eubacteria reported thus far. the group phe ...198711542088
were the original eubacteria thermophiles?thermotoga maritima is one of the more unusual eubacteria: it is highly thermophilic, growing at temperatures higher than any other eubacterium; its cell wall appears to have a unique structure and its lipids a unique composition; and the organism is surrounded by a loose-fitting sheath of unknown function. its phenotypic uniqueness is matched by its phylogenetic position; thermotoga maritima represents the deepest known branching in the eubacterial line of descent, as measured by ribosomal rn ...198711542087
purification and characterization of a highly stable tyrosinase from thermomicrobium roseum.tyrosinase, with an isoelectric point at ph 4.9, was purified to electrophoretic homogeneity from an extremely thermophilic bacterium, thermomicrobium roseum. gel filtration, n-terminal amino acid sequencing and sds/page analysis indicate that t. roseum tyrosinase is composed of two identical subunits, each with a molecular mass of 43000 da. the enzyme exhibited high substrate specificity towards catechol, chlorogenic acid, l-3-(3,4-dihydroxyphenyl)-l-alanine (l-dopa) and pyrogallol. the k(m) va ...200010744956
discontinuous occurrence of the hsp70 (dnak) gene among archaea and sequence features of hsp70 suggest a novel outlook on phylogenies inferred from this protein.occurrence of the hsp70 (dnak) gene was investigated in various members of the domain archaea comprising both euryarchaeotes and crenarchaeotes and in the hyperthermophilic bacteria aquifex pyrophilus and thermotoga maritima representing the deepest offshoots in phylogenetic trees of bacterial 16s rrna sequences. the gene was not detected in 8 of 10 archaea examined but was found in a. pyrophilus and t. maritima, from which it was cloned and sequenced. comparative analyses of the hsp70 amino aci ...19999882656
evolutionary variation in bacterial rnase p rnas.sequences encoding rnase p rnas from representatives of the last remaining classical phyla of bacteria have been determined, completing a general phylogenetic survey of rnase p rna sequence and structure. this broad sampling of rnase p rnas allows some refinement of the secondary structure, and reveals patterns in the evolutionary variation of sequences and secondary structures. although the sequences range from 100 to <25% identical to one another, and although only 40 of the nucleotides are in ...19989722626
characterization of novel long-chain 1,2-diols in thermus species and demonstration that thermus strains contain both glycerol-linked and diol-linked this study, we purified and characterized tetra- and triglycosyl glycolipids (gl-1 and gl-2, respectively) from two different colonial forms of thermus scotoductus x-1, from t. filiformis tok4 a2, and from t. oshimai sps-11. acid hydrolysis of the purified glycolipids liberated, in addition to the expected long-chain fatty acids, two components which were identified by gas chromatography-mass spectrometry as 16-methylheptadecane-1,2-diol and 15-methylheptadecane-1,2-diol. fast atom bombardmen ...19979324266
sequencing of heat shock protein 70 (dnak) homologs from deinococcus proteolyticus and thermomicrobium roseum and their integration in a protein-based phylogeny of prokaryotes.the 70-kda heat shock protein (hsp70) sequences define one of the most conserved proteins known to date. the hsp70 genes from deinococcus proteolyticus and thermomicrobium roseum, which were chosen as representatives of two of the most deeply branching divisions in the 16s rrna trees, were cloned and sequenced. hsp70 from both these species as well as thermus aquaticus contained a large insert in the n-terminal quadrant, which has been observed before as a unique characteristic of gram-negative ...19978990285
the atypical cell wall composition of thermomicrobium roseum.the cell wall of thermomicrobium roseum, a gram-negative, obligately thermophilic bacterium, has a composition unlike other gram-negative thermophilic organisms. the purified cell wall was composed predominantly of a protein with a monomeric molecular weight of 75 000. the amino acid composition of this protein revealed high concentrations of proline, glutamic acid, glycine, and alanine.19807378949
effect of growth temperature on the long-chain diols and fatty acids of thermomicrobium roseum.long-chain 1,2-diols constitute the hydrophobic backbone of membrane lipids (replacing glycerolipids) in the thermophilic eubacterium thermomicrobium roseum. the effects of incubation temperature on chain length and chain branching of diols and fatty acids were investigated. the percentage of branched chains decreased, and chain length increased slightly, with increased growth temperatures.19873818547
5s rrna sequences of representatives of the genera chlorobium, prosthecochloris, thermomicrobium, cytophaga, flavobacterium, flexibacter and saprospira and a discussion of the evolution of eubacteria in general.5s rrna sequences were determined for the green sulphur bacteria chlorobium limicola, chlorobium phaeobacteroides and prosthecochloris aestuarii, for thermomicrobium roseum, which is a relative of the green non-sulphur bacteria, and for cytophaga aquatilis, cytophaga heparina, cytophaga johnsonae, flavobacterium breve, flexibacter sp. and saprospira grandis, organisms allotted to the phylum 'bacteroides-cytophaga-flavobacterium' and relatives as determined by 16s rrna analyses. by using a cluste ...19901693658
purification and some properties of a thermostable metal proteinase produced by thermomicrobium sp. kn-22 extreme thermophile that produces a heat-stable proteinase was isolated from hot-spring water and classified as thermomicrobium sp. kn-22 (growth temperature, 50-83 degrees c; and optimum growth temperature, 70 degrees c). the proteinase was purified from the culture broth of this strain by fractionation with ammonium sulfate, chromatography on columns of deae-cellulose and cm-sepharose cl-6b, and hplc on tskgel cm-5pw. the purified enzyme gave a single band on sds-polyacrylamide gel electrop ...19911368714
Displaying items 1 - 18 of 18