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1.
The desulfurization activity of the resting cells of Gordona sp. CYKS1 was strongly depended on harvest time and the highest value when the cells had been harvested in the early growth phase (0.12 mg sulfur g–1 cell–1 h–1). For the model oil, hexadecane containing dibenzothiophene, the specific desulfurization rate decreased as the reaction proceeded. Both the specific and the volumetric desulfurization rates were not significantly affected by the aqueous-to-oil phase ratio. The diesel oils, light gas oil and a middle distillate unit feed were desulfurized at higher rates (ca. 0.34 mg sulfur g–1 cell–1 h–1) than the model oil (0.12 mg sulfur g–1 cell–1 h–1). 相似文献
2.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1270-1275
A bacterial strain, designated CY22, was isolated from the interior of balloon flower (Platycodon grandiflorum) root in the Republic of Korea. The isolate coproduced an iturin-like antifungal compound and a surfactin-like potent biosurfactant. Analysis of the 16S-rDNA of strain CY22 showed that the isolate was a member of Bacillus. High similarities were observed between strain CY22 and Bacillus sp. TKSP 24, and between strain CY22 and B. subtilis 168. Phylogenetic analysis based on 16S-rDNA sequences showed that strain CY22 was closely related to Bacillus sp. The main whole-cell fatty acids were anteiso-C15:0 (37%), C17:0 (5.1%), and iso-C15:0 (27.7%). DNA G + C content was 54 mol%. Based on phylogenetic inference, phenotypic and chemotaxonomic characteristics, this endophytic strain Bacillus sp. CY22 was assigned to the genus Bacillus. 相似文献
3.
Sacramento Doralice Rodrigues Coelho Rosalie Reed Rodrigues Wigg Márcia Dutra Toledo Luna Linhares Luiz Fernando de Matos dos Santos Marta Gonçalves Azevedo Soares Semêdo Luzia Teixeira de Ribeiro da Silva Antonio Jorge 《World journal of microbiology & biotechnology》2004,20(3):225-229
A promising producer of bioactive compounds isolated from a Brazilian tropical soil was tested for its range of antimicrobial
activities. Strain 606, classified as Streptomyces sp., could not be identified up to species level, suggesting a possible new taxon. The supernatant and 10 extracts and fractions,
obtained by extraction and chromatographic techniques, presented antimicrobial activity using antibiograms. The methanolic
fraction was highly active against pathogenic bacteria, phytopathogenic fungi and the human pathogenic yeast Candida albicans. It also possessed high antiviral activity inhibiting the propagation of an acyclovir-resistant herpes simplex virus type
1 strain on HEp-2 cells at non-cytotoxic concentration. The strong cytotoxic effect suggests an antitumour action.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
V. Grant 《Plant Systematics and Evolution》2001,230(1-2):89-96
This paper deals with the use of cladistic methods and cladograms in phylogeny reconstruction in plant groups containing
numerous taxa. How accurate are the cladograms as to details? Accuracy tests at the level of details require an independently
known phylogeny, which excludes most plant groups, but such tests can be carried out in domesticated and experimental plant
groups which have documented pedigrees. Four such tests are known and are presented here: a new case in Gilia and three previously published cases in Avena, Hordeum, and Helianthus. The four cases include domesticated and experimental plants, use of morphological and molecular evidence, and presence of
dichotomous as well as reticulate phylogenies. The cladograms of the four plant groups all differ in significant details from
the known pedigrees. These results are discussed in relation to problems of interpretation of cladograms.
Received March 21, 2000 Accepted August 16, 2001 相似文献
5.
Genes for the biosynthesis of spinosyns: applications for yield improvement in Saccharopolyspora spinosa 总被引:2,自引:0,他引:2
K Madduri C Waldron P Matsushima M C Broughton K Crawford D J Merlo R H Baltz 《Journal of industrial microbiology & biotechnology》2001,27(6):399-402
Spinosyns A and D are the active ingredients in an insect control agent produced by fermentation of Saccharopolyspora spinosa. Spinosyns are macrolides with a 21-carbon, tetracyclic lactone backbone to which the deoxysugars forosamine and tri-O-methylrhamnose are attached. The spinosyn biosynthesis genes, except for the rhamnose genes, are located in a cluster that
spans 74 kb of the S. spinosa genome. DNA sequence analysis, targeted gene disruptions and bioconversion studies identified five large genes encoding type
I polyketide synthase subunits, and 14 genes involved in sugar biosynthesis, sugar attachment to the polyketide or cross-bridging
of the polyketide. Four rhamnose biosynthetic genes, two of which are also necessary for forosamine biosynthesis, are located
outside the spinosyn gene cluster. Duplication of the spinosyn genes linked to the polyketide synthase genes stimulated the
final step in the biosynthesis — the conversion of the forosamine-less pseudoaglycones to endproducts. Duplication of genes
involved in the early steps of deoxysugar biosynthesis increased spinosyn yield significantly. Journal of Industrial Microbiology & Biotechnology (2001) 27, 399–402.
Received 31 May 2001/ Accepted in revised form 09 July 2001 相似文献
6.
Bidens cordylocarpa is a high polyploid species restricted in distribution to stream sides in the mountains of Jalisco, Mexico. The morphologically
enigmatic species was originally described as a member of the genus Coreopsis, but later transferred to Bidens, largely because the involucral bracts appear most similar to Bidens. Characters of the cypselae, often useful in generic placement, are of no value for this species because the fruits have
features not detected in either Bidens or Coreopsis. Sequences from the internal transcribed spacer region of nuclear ribosomal DNA (ITS) were used to assess the relationships
of Bidens cordylocarpa. The molecular phylogeny places B. cordylocarpa in a strongly supported clade of Mexican and South American Bidens, and provides more definitive evidence of relationships than morphology, chromosome number, or secondary chemistry. Molecular,
morphological, and chromosomal data suggest that B. cordylocarpa is an ancient polyploid, perhaps the remnant of a polyploid complex.
Received August 28, 2000 Accepted February 11, 2001 相似文献
7.
Gregory L. Dilworth 《Archives of biochemistry and biophysics》1982,219(1):30-38
The nicotinic acid hydroxylase from Clostridium barkeri is a selenoenzyme, as evidenced by the copurification of selenium with enzyme activity. This conclusion is supported by data showing a 23-fold increase in nicotinic acid hydroxylase activity when C. barkeri was cultured in media supplemented with selenium. A labile, selenium-containing compound was released from the native protein by treatment with either chaotropic agents and heat or by heating alone. A stable selenium compound was formed when the enzyme was alkylated prior to denaturation. This compound had the same chromatographic properties as dialykyl selenide in a number of systems. The formation of dialkyl selenide upon alkylation is not consistent with the selenium moiety being selenocysteine. Thus, nicotinic acid hydroxylase represents a new type of selenoenzyme. 相似文献
8.
M. Y. Shukor M. F. Rahman Z. Suhaili N. A. Shamaan M. A. Syed 《World journal of microbiology & biotechnology》2009,25(7):1225-1234
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated
from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny.
ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such
as Serratia
marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as
sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that
supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction
exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium,
silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at
1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation. 相似文献
9.
Formation of a Tree having a Low Lignin Content 总被引:2,自引:0,他引:2
Received 30 September 2001/ Accepted in revised form 26 October 2001 相似文献
10.
The l-thyroxine binding site in human serum thyroxine-binding globulin was investigated by affinity labeling with N-bromoacetyl-l-thyroxine (BrAcT4). Competitive binding studies showed that, in the presence of 100 molar excess of BrAcT4, binding of thyroxine to thyroxine-binding globulin was nearly totally abolished. The reaction of BrAcT4 to form covalent binding was inhibited in the presence of thyroxine and the affinity-labeled thyroxinebinding globulin lost its ability to bind thyroxine. These results indicate BrAcT4 and thyroxine competed for the same binding site. Affinity labeling with 2 mol of BrAcT4/mol of thyroxine-binding globulin resulted in the covalent attachment of 0.7 mol of ligand. By amino acid analysis and high voltage paper electrophoresis, methionine was identified as the major residue labeled (75%). Lysine, tyrosine, and histidine were also found to be labeled to the extent of 8, 8, and 5%, respectively. 相似文献