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1.
The cell wall of Bacillus subtilis VKM B-762 contains, along with 1,5-poly[4-O-(2-acetamido-2-deoxy-β-d-glucopyranosyl)ribitol phosphate], a novel type of glycopolymer involving three types of inter-monomeric bonds in the repeating unit, viz., amide, glycosidic and phosphodiester:Such a structural pattern of natural glycopolymers has been hitherto unknown. This polymer represents a novel type of teichoic acids.  相似文献   

2.
The cell walls of Actinomadura carminata INA 4281 were found to contain peptidoglycan, teichoic acid, and nonpeptidoglycan amino acids. The peptidoglycan was of the A1 type and contained a small amount of ll-DAP in addition to m-DAP. The teichoic acid was an 1,3-poly(glycerol phosphate) chain composed of about eight glycerophosphate units, two of which had a 2-acetamido-2-deoxy--d-galactopyranosyl substituent and one, a 3-O-methyl--d-galactopyranosyl-(1 3)-2-acetamido-2-deoxy--d-galactopyranosyl residue at C2 of glycerol. The structure of the polymer was identified by chemical analysis and 13C-NMR spectroscopy. The teichoic acid contained 3-O-methyl-d-galactose (madurose) — the first ever finding of this compound within a teichoic acid. The nonpeptidoglycan amino acids made up some 30% of the cell wall's dry weight, about a quarter of the amino acids being removable with sodium dodecyl sulfate. Further treatment of the cell walls with LiCl and guanidine hydrochloride caused only a small loss of the amino acids and slight changes in their molar ratio.Abbreviations Gro glycerol - GroP monophosphate glycerol - GroP2 diphosphate glycerol - Gro2P -monophosphate glycerol - PTA phosphorus of teichoic acids - PNA phosphorus of nucleic acids - TA teichoic acid  相似文献   

3.
Twenty coryneform bacteria identified as Brevibacterium linens or related strains from different private and public collections were studied biochemically in respect to the composition of the cell walls and in respect to the nucleic acid hybridisation. Investigation of the cell walls revealed an identical meso-diaminopimelic acid containing directly cross-linked peptidoglycan type which is not amidated. The characteristic polymers of the polysaccharide moiety of the cell walls were found to be teichoic acids which belong to the poly(glycerolphosphate) and the poly(ribitolphosphate) type. Furthermore a novel mannitol containing teichoic acid is present which is tentatively characterized as poly(mannitolphosphate). Arabinoglactan and ribose as distinctive sugar components together with galactose and glucose in the cell walls of B. linens could not be detected in any strain. The biochemical findings lend support to the view that B. linens and related strains form a distinctive group which is clearly distinguished from all other coryneform bacteria. This is supported by DNA-23S/16S ribosomal ribonucleic acid reassociation studies. Deoxyribonucleic acid-deoxyribonucleic acid homology studies show the incoherency of B. linens which obviously comprises two species.  相似文献   

4.
An attempt has been made to identify proteins synthesised during induction of teichoic acid synthesis in Bacillus licheniformis ATCC 9945. The proteins are recognised as those produced on the change from teichuronic acid to teichoic acid synthesis that occurs after the transfer of the bacteria from phosphate-limited to phosphate-rich conditions. B. licheniformis was grown in phosphate-limiting conditions in the presence of threonine to stimulate threonine uptake. The bacteria were then transferred to phosphate-rich conditions and were pulsed-labelled with [14C]threonine during the change to teichoic acid synthesis. All of the proteins were extracted from the cells with sodium dodecyl sulphate and were examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Radioactive polypeptides were identified by fluorography of the polyacrylamide gels. The radioactive polypeptides that were formed on change from teichuronic acid to teichoic acid synthesis were compared with the polypeptides present in a membrane sub-fraction that had high teichoic acid-synthesising activity. The labelling of nine polypeptides with [14C]threonine was dependent on new RNA synthesis. Of these nine polypeptides, five were also present in the membrane sub-fraction with the highest teichoic acid-synthesising activity.  相似文献   

5.
Purified cell walls, originating from penicillin-treated (3 g/ml, 1 h) and-untreated Brevibacterium divaricatum cells grown on complex (CM) and glucose minimal medium with (MM) or without (Ca-free MM) calcium carbonate, were isolated by two procedures. Electron micrographs and chemical analysis revealed no differences between identically isolated walls with respect to the presence or absence of either penicillin or calcium carbonate in the glucose growth medium. On the contrary, the appearance and peptidoglycan content of the walls was greatly dependent on the procedure used for their isolation and the walls isolated from the cells grown on complex medium contained more materials other than peptidoglycan. It was shown that the presence of calcium carbonate in the glucose minimal medium was essential for accumulation of large amounts of peptidoglycan chains into the medium. Penicillin-induced interruption of cell wall synthesis was prerequisite for manifestation of the calcium carbonate stimulating effect.Abbreviations CM complex medium - MM chemically defined minimal medium based on glucose and containing calcium carbonate - Ca-free MM MM modified only by the omission of calcium carbonate - ET-walls Enzyme treated walls - FPR-walls French press-ruptured walls  相似文献   

6.
James L. Luteyn 《Brittonia》2001,53(3):437-446
Satyria ventricosa andVaccinium monteverdense from Panama and Costa Rica, respectively, are described and illustrated.Gonocalyx megabracteolatus andVaccinium talamancense are new combinations. Relationships of the new species are discussed. Keys are provided for the entire genusGonocalyx, and forSatyria in Mesoamerica.
Resumen  Se describenSatyria ventricosa yVaccinium monteverdense de Panamá y Costa Rica, respectivamente, con sus ilustraciones. Se hace una nueva combinación deGonocalyx megabracteolatus yVaccinium talamancense. También se discuten las relaciones entre las nuevas especies. Se incluyen claves para el género completoGonocalyx y para el géneroSatyria en Mesoamérica.
  相似文献   

7.
8.
The cell wall of Actinoplanes philippinesis VKM Ac-647 harbours several carbohydrate-containing anionic polymers. (1) The main polymer of the wall is of a poly(glycosylglycerol phosphate) nature. Its monomeric units — O--d-mannopyranosyl-(14)--d-galactopyranosyl-(11)-glycerol monophosphates — are connected by phosphodiester bonds involving the hydroxyl groups at glycerol C3 and galactose C6. There also are chains without mannosyl substitutents. The teichoic acid structure has been established by chemical analysis and with 1H and 13C NMR spectroscopy. This is the first finding of a teichoic acid with mannosyl residues in a bacterial cell wall. (2) The phosphorylated mannan contains mannose and 2-O-methylmannose. Its core chain has -1,2; -1,3; and -1,6 substitutions as revealed by 13C NMR spectroscopy.The peptide unit of the peptidoglycan contains no l-alanine, instead of which position 1 is occupied by glycine; and diaminopimelic acid is represented, besides its meso- (or DD) form, by small amounts of its LL isomer.Abbreviations Gro glycerol - Gro2P glycerol-2 phosphate - APT attached-proton-test - Ptot total content of phosphorus - Plab phosphorus mineralized in 7 min at 100°C - PNA phosphorus of nucleic acids - Pstab stable phosphorus - T trace amounts  相似文献   

9.
华西南毛茛科六新种和二新变种   总被引:1,自引:0,他引:1  
王文采 《广西植物》2013,(5):579-587
该文描述了自华西南东部发现的毛茛科翠雀属2新种和1新变种、唐松草属1新种、银莲花属1新种和1新变种,以及毛茛属2新种。  相似文献   

10.
A sponge-associated marine actinomycetes Nocardiopsis alba MSA10 was screened and evaluated for the production of biosurfactant. Biosurfactant production was confirmed by conventional screening methods including hemolytic activity, drop collapsing test, oil displacement method, lipase production and emulsification index. The active compound was extracted with three solvents including ethyl acetate, diethyl ether and dichloromethane. The diethyl ether extract was fractionated by TLC and semi-preparative HPLC to isolate the pure compound. In TLC, a single discrete spot was obtained with the R f 0.60 and it was extrapolated as valine. Based on the chemical characterization, the active compound was partially confirmed as lipopeptide. The optimum production was attained at pH 7, temperature 30°C, and 1% salinity with glucose and peptone supplementation as carbon and nitrogen sources, respectively. Considering the biosurfactant production potential of N. alba, the strain could be developed for large-scale production of lipopeptide biosurfactant.  相似文献   

11.
王文采 《广西植物》2016,36(Z1):76-84
该文描述了自华西南东部发现的毛茛科翠雀属2新种和1新变种、唐松草属1新种、银莲花属1新种和1新变种,以及毛茛属2新种。  相似文献   

12.
Conditions are described for the continuous culture of a derivative of Staphylococcus aureus H in a fully defined minimal medium in which cysteine is the sole amino acid. The effects of growth under various nutrient limitations on the composition and properties of the cell wall have been studied. The proportion of ribitol teichoic acid present in the wall, and the extent to which it is substituted with N-acetylglucosamine, varies in bacteria grown under different conditions as does the composition and extent of cross-linking of the peptidoglycan. Neither the derivative nor the original strain H produced teichuronic acid when grown under phosphate limitation.Non-Standard Abbreviation SDS Sodium dodecyl sulphate  相似文献   

13.
The free fatty acid and phospholipid composition of 4 psychrophilic marineVibrio spp. have been determined in chemostat culture with glucose as the limiting substrate over a temperature range 0–20°C. All the isolates show maximum glucose and lactose uptake at 0°C and this correlates with maximum cell yield. None of the isolates contain fatty acids with a chain length exceeding 17 carbon atoms.Vibrio AF-1 andVibrio AM-1 respond to decreased growth temperatures by synthesizing increased proportions of unsaturated fatty acids (C15:1, C16:1 and C17:1) whereas inVibrio BM-2 the fatty acids undergo chain length shortening. The fourth isolate (Vibrio BM-4) contains high levels (60%) of hexadecenoic acid at all growth temperatures and the fatty acid composition changes little with decreasing temperature. The principal phospholipid components of the four psychrophilic vibrios were phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. Lyso-phosphatidylethanolamine and 2 unknown phospholipids were additionally found inVibrio AF-1. The most profound effect of temperature on the phospholipid composition of these organisms was the marked increase in the total quantities synthesized at 0°C. At 15°C phosphatidylglycerol accumulated in the isolates as diphosphatidylglycerol levels decreased. Additionally inVibrio BM-2 andVibro BM-4 phosphatidylserine accumulates as phosphatidylethanolamine biosynthesis was similarly impaired. The observed changes in fatty acid and phospholipid composition in these organisms at 0°C may explain how solute transport is maintained at low temperature.Abbreviations PS Phosphatidylserine - PE phosphatidylethanolamine - PG phosphatidylglycerol - DPG diphosphatidylglycerol - lyso PE lysophosphatidylethanolamine  相似文献   

14.
Phytochemical investigation of the rhizome of Dioscorea dumetorum has led to the isolation by several chromatographic steps on normal and reversed phase silica gel of a new ecdysteroid, (20R)-5β,11α,20-trihydroxyecdysone (1), and two known ecdysteroids, ajugasterone C (2) and herkesterone (3). Their structures were determined by spectroscopic methods including 1D- and 2D-NMR (COSY, TOCSY, HSQC and HMBC). This is the first report on the occurrence of phytoecdysteroids in the Dioscoreaceae family. These compounds were devoid of antifungal activity against three Candida species (Candida albicans, Candida glabrata and Candida tropicalis, MIC > 200 μg/ml).  相似文献   

15.
Described as new areHypolytrum pallidiceps, a clearcut species from Guyana,Oreobolus ecuadorensis, an ally ofO. obtusangulus from Ecuador, andScleria millespicula of the sectionOphryoscleria from Brazilian Amazonia.Oreobolus venezuelensis andScleria sprucei are newly added to the floras of Colombia and Venezuela respectively. Part I. Jap. J. Bot.20(2): 123–134. 1969.  相似文献   

16.
17.
The sponge-associated actinomycetes were isolated from the marine sponge Dendrilla nigra, collected from the southwest coast of India. Eleven actinomycetes were isolated depending upon the heterogeneity and stability in subculturing. Among these, Nocardiopsis dassonvillei MAD08 showed 100% activity against the multidrug resistant pathogens tested. The culture conditions of N. dassonvillei MAD08 was optimized under submerged fermentation conditions for enhanced antimicrobial production. The unique feature of MAD08 includes extracellular amylase, cellulase, lipase, and protease production. These enzymes ultimately increase the scope of optimization using broad range of raw materials which might be efficiently utilized. The extraction of the cell free supernatant with ethyl acetate yielded bioactive crude extract that displayed activity against a panel of pathogens tested. Analysis of the active thin layer chromatography fraction by Fourier transform infrared and gas chromatography-mass spectrometry evidenced 11 compounds with antimicrobial activity. The ammonium sulfate precipitation of the culture supernatant at 80% saturation yielded an anticandidal protein of molecular weight 87.12 kDa. This is the first strain that produces both organic solvent and water soluble antimicrobial compounds. The active extract was non-hemolytic and showed surface active property envisaging its probable role in inhibiting the attachment of pathogens to host tissues, thus, blocking host–pathogen interaction at an earlier stage of pathogenesis.  相似文献   

18.
The simultaneous occurrence of a N-acetylglucosaminyl poly(ribitolphosphate) (-GlcNAc) and a N-acetylglucosaminyl poly(glycerolphosphate) (-GlcNAc) in the cell walls of Staphylococcus xylosus DSM 20266 was demonstrated by different experimental lines:(1) Fractionation of extracted cell wall teichoic acid on DEAE-cellulose, (2) investigation of the composition of cell walls in the growth cycle, (3) in vitro biosynthesis using crude membranes as the source of enzyme.The polymerization of these polymers starts from CDP-ribitol and CDP-glycerol, respectively. In the presence of UDP-N-acetylglucosamine both polymers are substituted with N-acetylglucosamine at a level and with the identical anomeric configuration found in the native cell wall teichoic acids. The in vitro biosynthesis of poly(glycerolphosphate) was unique in that it was highly stimulated by UDP-N-acetylglucosamine and to a lower extent by other UDP-activated sugars. Kinetic studies have provided evidence that this stimulation is due to an increase of V max while K m is unchanged. Competition experiments have indicated that poly(ribitolphosphate) and poly(glycerolphosphate) were synthesized in the in vitro system in a close spatial relationship.Abbreviations ADP adenosine 5-diphospho - CDP cytidine 5-diphospho - GDP guanosine 5-diphospho - GalNAc N-acetyl-galactosamine - Glc glucose, glucosyl - GlcNAc N-acetyl-glucosamine - N acetylglucosaminyl - GlcUA glucuronic acid - Gro glycerol - Man mannose, mannosyl - Rit ribitol - SDS sodium dodecyl sulfate - UDP uridine 5-diphospho  相似文献   

19.
The structures of two teichoic acid fractions (TA1 and TA2) isolated from the thermophilic gram-positive bacterium Geobacillus thermoleovorans strain Fango were investigated by means of chemical and NMR spectroscopic methods. The most abundant species (TA1) exhibited a rather regular structure comprising two different repeating units of 1,3-glycerol phosphate nonstoichiometrically substituted by terminal-alpha-D-Gal p (t-alpha-D-Gal p). The second molecular species (TA2) presented a higher structural variability and t-alpha-D-Glc p and the disaccharides t-alpha-D-Glc pNAc-(1-->2)-alpha-D-Glc p and t-alpha-D-Glc pNAc-(1-->3)-alpha-D-Glc p were also present as minor substituents at O-2 of the glycerol phosphate residues. Minor substitution by alanine could also be detected.  相似文献   

20.
Ubiquinone system, GC contents and cellular fatty acid (CFA) composition were analyzed as criteria for chemotaxonomy ofMalbranchea species andCoccidioides immitis, which are suggested to be phylogenetically related. Based on the major ubiquinone,Malbranchea spp. were divided into two groups, of which one group possessed the same major ubiquinone asC. immitis. Similar GC contents and CFA profiles were obtained for the species ofMalbranchea andC. immitis. On the basis of these criteria the relationships between the fungi are discussed.  相似文献   

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