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1.
The structures of cell wall teichoic acids of the members of newly recognized genera of the order Actinomycetales were studied. Planotetraspora mira VKM Ac-2000T contains two types of teichoic acids: 2,3-poly(glycerol phosphate) substituted with -D-Galp at C-1 of glycerol and 1,3-poly(glycerol phosphate) substituted with -L-Rhap at OH-2 of glycerol (60%). Herbidospora cretacea VKM Ac-1997T contains the chains of 1,3-poly(glycerol phosphate) partially substituted with -D-Galp and -D-GalpNAc at C-2 of glycerol. The majority of -D-galactopyranosyl residues are substituted at OH-3 with a sulfate. The aforementioned teichoic acids have not been found in bacteria thus far. Actinocorallia herbida VKM Ac-1994T contains poly(galactosylglycerol phosphate), with the -Galp-(12)-Gro-P repeating units being linked via the phosphodiester bonds between the OH-3 of glycerol and OH-6 of galactose. Earlier, this structure was found in the cell wall of Actinomadura madura. The polymer structures were determined by chemical analysis and using 13C-NMR spectroscopy. The results show that teichoic acids are widespread in the order Actinomycetales.  相似文献   

2.
Potekhina  N. V.  Shashkov  A. S.  Evtushenko  L. I.  Naumova  I. B. 《Microbiology》2003,72(2):157-161
The cell walls of Microbispora mesophila strain Ac-1953T (the family Streptosporangiaceae) and Thermobifida fusca Ac-1952T (the family Nocardiopsaceae) were found to contain teichoic acids of a poly(glycerol phosphate) nature. The teichoic acid of M. mesophila (formerly Thermomonospora mesophila) represents a 1,3-poly(glycerol phosphate) containing 5% of substituent 2-acetamido-2-deoxy--D-galactosaminyl residues. Teichoic acid of such a kind was found in actinomycetes for the first time. The cell wall of T. fusca (formerly Thermonospora fusca) contains two teichoic acids, namely, unsubstituted 1,3-poly(glycerol phosphate) and -glucosylated 1,3-poly(glycerol phosphate).  相似文献   

3.
Novel O-serotypes were revealed among Pseudomonas syringae pv. garcae strains by using a set of mouse monoclonal antibodies specific to the lipopolysaccharide O-polysaccharide. Structural studies showed that the O-polysaccharide of P. syringae pv. garcae NCPPB 2708 is a hitherto unknown linear L-rhamnan lacking strict regularity and having two oligosaccharide repeating units I and II, which differ in the position of substitution in one of the rhamnose residues and have the following structures: I:3)--L Rha (12)-- L Rha (12)--L-Rha-(13)--L Rha (1;II: 2)--L-Rha-(13) -L-Rha-(12)--L-Rha-(13)--L Rha (1.The branched O-polysaccharides of P. syringae pv. garcae ICMP 8047 and NCPPB 588T have the same L-rhamnan backbone with repeating units I and II and a lateral chain of 14)- or 13)-linked residues of 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc). Several monoclonal antibody epitopes associated with the L-rhamnan backbone or the lateral -D-Fuc3NAc residues were characterized.Translated from Mikrobiologiya, Vol. 73, No. 6, 2004, pp. 777–789.Original Russian Text Copyright © 2004 by Ovod, Zdorovenko, Shashkov, Kocharova, Knirel.  相似文献   

4.
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   

5.
-Cyfluthrin [-cyano-4-fluoro-3-phenoxybenzyl-3(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate] pesticide has been in agricultural use in the recent years for controlling Lepidopteran pests affecting solanaceous crops. The extensive use of synthetic pyrethroids like -cyfluthrin has resulted in wide spread environmental contamination. The purpose of this study was to isolate bacteria from soil and to determine their ability to degrade -cyfluthrin and identify the intermediates in culture broth using spectroscopy. An aerobic bacterium capable of degrading -cyfluthrin was isolated by enrichment culture. The 16S ribosomal DNA sequence of the isolate (strain S1) had 100% identity to the sequence from Pseudomonas stutzeri. Finally products formed during degradation of -cyfluthrin have been identified as -cyano-4-fluoro-3-phenoxybenzyl-3(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate (M.W. 341); 4-fluoro-3-phenoxy--cyanobenzyl alcohol (M.W. 243) and 3(2,2-dichlorovinyl)-2,2-dimethyl cyclopropanecarboxylic acid (M.W. 208).  相似文献   

6.
Partly biosynthetic site-directed isotopically 13C enriched photosynthetic light-harvesting 2(LH2) complexes have been prepared from Rhodopseudomonas acidophila strain 10050 by using chemically labeled [1,2,3,4–13C], [1,4–13C] and [2,3–13C] succinic acid as a precursor in the growth medium. Two-dimensional proton driven spin diffusion (PDSD) solid state NMR correlation spectroscopy has been used to trace each individual 13C isotope from the labeled succinic acid precursor to its destination into the protein and into the embedded major light-absorbing bacteriochlorophyll cofactors. For both the residues of the protein and for the cofactors distinct labeling patterns have been deduced, for protein complexes prepared from [1,4–13C]-succinic acid or [2,3–13C]-succinic labeled media. All residues, except isoleucine and leucine, have been labeled almost homogeneously by the succinic acid precursor. Carbonyl carbons in the protein backbone were labeled by [1,4–13C]-succinic acid, while the C and C carbons of the residues were labeled by [2,3 13C]-succinic acid. Leucine and isoleucine residues were labeled using a uniformly labeled amino acid mixture in the medium. The pattern labeling yields an increase of the resolution and less spectral crowding. The partial labeling technique in combination with conventional solid state NMR methods at ultra high magnetic fields provides an attractive route to resolve chemical shifts for -helical transmembrane protein structures.  相似文献   

7.
Structurally identical teichoic acids were detected in cell walls of two soil isolates assigned to Brevibacterium linens based on phylogenetic data. Both cell walls contain unsubstituted 1,3-poly(glycerol phosphate) and poly(glycosylglycerol phosphate). Repeating units of the latter--alpha-D-GlcpNAc-(1-->4)-beta-D-Galp-(1-->1)-Gro--are bound by phosphodiester bonds including OH-3 of galactose and OH-3 of glycerol. Some of the N-acetylglucosamine residues have 4,6-pyruvic acid acetal, amounts of the latter in the two strains being unequal. Species-specificity of the structures of teichoic acids in the genus Brevibacterium is discussed.  相似文献   

8.
Summary The distribution of cholinergic neurons in the urinary tract and male genital organs of the cat was studied by a histochemical method for acetylcholinesterase. In addition to cell clusters in autonomic ganglia (intraganglionic cells), isolated extraganglionic cholinergic cells were found within the innervated tissues, usually in association with nerve trunks and blood vessels. Smaller neural cells with multiple axonal processes, identical to Cajal's interstitial cells, were found in the meshes of the terminal nerve plexus in smooth muscle, lamina propria and vascular wall.It is concluded that peripheral cholinergic neurons, like their adrenergic analogues, are arranged as a short intraganglionic, a shorter extraganglionic, and a terminal system of neurons.Supported in part by grants 10465 and 11285 from the USPHS and the Henry C. Buswell Urology Research Fund.  相似文献   

9.
Li ZY  Li YJ  Guo CY  Shi YW  Xu MQ  Trommer WE  Yuan JM 《Biotechnology letters》2004,26(23):1765-1769
An open reading frame of the -subunit 1-205 residues (205) of human acetylcholine receptor (AchR) was amplified by PCR with pUC-AChR205 as the template and inserted into vector pMAL-c2X. The constructed pMAR205 was transferred into E. coli BL21 which were then grown in LB medium. The amount of soluble MBP-AChR205 protein reached about 25% of total soluble proteins from the cell lysate. Using amylose-affinity chromatography, about 35 mg MBP-AChR205 could be obtained from 1 l culture. Western blot analysis and ELISA showed that immunoreactivities of both MBP-AChR205 and AChR205 were similar to that of AChR -subunit from Torpedo.Revisions received 23 September 2004  相似文献   

10.
Fang-Sheng Wu 《Planta》1987,171(3):346-357
The positively-charged fluorescent dye rhodamine 123 (r-123) specifically stains mitochondria in living plant protoplasts, suspensionculture cells, and root hairs. This dye functions as a vital stain and permits visualization of the localization, distribution and movement of the mitochondria. Dehydration of root hairs caused mitochondria to aggregate into clumps. Mitochondria were either homogenous or heterogeneous and were frequently seen to accumulate in the perinuclear regions of suspension-culture cells but not in those of protoplasts or root-hair cells. Dinitrophenol and high concentrations of ethyleneglycol-bis(-aminoethyl ether)-N,N,N,N-tetraacetic acid and KCl immediately eliminated fluorescence in r-123-stained mitochondria whereas ionomycin enhanced it. Treatment of seedlings with r-123 resulted in differential brightness of fluorescence in different tissues. Meristematic tissues, such as root and shoot tips, exhibited the brightest fluorescence. The cytotoxicity of r-123 in both germinating seedlings and suspension-culture cells was low. The specificity, sensitivity and low toxicity of r-123 should make it a useful tool in experiments designed to examine agents and conditions which affect the location, the physiological status or the viability of mitochondria.Abbreviations EGTA ethyleneglycol-bis-(-aminoethyl ether)N,N,N,N-tetraacetic acid - DAPI 46-diamidino-2-phenylindole - r-123 rhodamine 123  相似文献   

11.
The cell wall anionic polymers of the 13 species of the Streptomyces cyaneus cluster have a similar structure and contain -glucosylated 1,5-poly(ribitol phosphate) and 1,3-poly(glycerol phosphate). In the degree of glucosylation of the ribitol phosphate units of their teichoic acids, the cluster members can be divided into two groups. The streptomycetes of the first group (S. afghaniensis, S. janthinus, S. purpurascens, S. roseoviolaceus, and S. violatus) are characterized by a very similar structure of their cell walls, the completely glucosylated 1,5-poly(ribitol phosphate) chains, and a high degree of DNA homology (67–88% according to literature data). The cell wall teichoic acids of the second group (S. azureus, S. bellus, S. caelestis, S. coeruleorubidus, S. curacoi, and S. violarus) differ in the degree of -glucosylation of their 1,5-poly(ribitol phosphate) chains and have a lower level of DNA homology (54–76% according to literature data). Two streptomycetes of the cluster (S. cyaneus and S. hawaiiensis) are genetically distant from the other cluster members but have the same composition and structure of the cell wall teichoic acids as the second-group streptomycetes. The data obtained confirm the genetic relatedness of the S. cyaneus cluster members and suggest that the structure of the cell wall teichoic acids may serve as one of the taxonomic criteria of the species-level status of streptomycetes.  相似文献   

12.
The spatial genetic structure was assessed by amplified fragment length polymorphism (AFLP) technique for Quercus crispula Blume (37 individuals) and Q.dentata Thunberg (54 individuals) growing along a 550-m transect in Ishikari, Hokkaido, northern Japan. The simple Mantel test revealed significant negative correlation between genetic similarity and geographic distance in Q.dentata and negative but insignificant correlation in Q.crispula. Spatial autocorrelation analysis revealed that Mantels r generally decreased from positive to negative values with the increase of spatial distance in both oak species with significant deviation from zero for the 50–100-m (positive) and 250–300-m classes (negative) in Q.dentata. Thus, significant spatial genetic structure was revealed at least in Q.dentata  相似文献   

13.
The peptidoglycan, the secondary cell wall polymer (SCWP), and the surface layer (S-layer) glycoprotein are the major glycosylated cell wall components of Paenibacillus alvei CCM 2051. In this report, the complete structure of the SCWP, its linkage to the peptidoglycan layer, and its physicochemical properties have been investigated. From the combined evidence of chemical and structural analyses together with one- and two-dimensional nuclear magnetic resonance spectroscopy, the following structure of the SCWP-peptidoglycan complex is proposed:[(Pyr4,6)--D-Manp NAc-(14)--D-Glcp NAc-(13)]ñ11-(Pyr4,6)--D-Manp NAc-(14)--D-Glcp NAc-(1O)-PO2-O-PO2-(O6)-MurNAc-Each disaccharide unit is substituted by 4,6-linked pyruvic acid residues. Under mild acidic conditions, up to 50% of them are lost, leaving non-substituted ManNAc residues. The anionic glycan chains constituting the SCWP are randomly linked via pyrophosphate groups to C-6 of muramic acid residues of the peptidoglycan layer. 31P NMR reveals two signals that, as a consequence of micelle formation, experience different line broadening. Therefore, their integral ratio deviates significantly from 1:1. By treatment with ethylenediaminetetraacetic acid, sodium dodecyl sulfate, and sonication immediately prior to NMR measurement, this ratio approaches unity. The reversibility of this behavior corroborates the presence of a pyrophosphate linker in this SCWP-peptidoglycan complex.In addition to the determination of the structure and linkage of the SCWP, a possible scenario for its biological function is discussed.  相似文献   

14.
Measurement of nitrogen isotopic composition (15N) of plants and soil nitrogen might allow the characteristics of N transformation in an ecosystem to be detected. We tested the measurement of 15N for its ability to provide a picture of N dynamics at the ecosystem level by doing a simple comparison of 15N between soil N pools and plants, and by using an existing model. 15N of plants and soil N was measured together with foliar nitrate reductase activity (NRA) and the foliar NO3 pool at two sites with different nitrification rates in a temperature forest in Japan. 15N of plants was similar to that of soil NO3 in the high-nitrification site. Because of high foliar NRA and the large foliar NO3 pool at this site, we concluded that plant 15N indicated a great reliance of plants on soil NO3 there. However, many 15N of soil N overlapped each other at the other site, and 15N could not provide definitive evidence of the N source. The existing model was verified by measured 15N of soil inorganic N and it explained the variations of plant 15N between the two sites in the context of relative importance of nitrification, but more information about isotopic fractionations during plant N uptake is required for quantitative discussions about the plant N source. The model applied here can provide a basis to compare 15N signatures from different ecosystems and to understand N dynamics.  相似文献   

15.
Organogenetic buds were induced from hypocotyl and cotyledon explants of oil crop Perilla frutescens in Murashige and Skoog (MS) medium supplemented with 5.7 M indole-3-acetic acid (IAA) and 8.9 – 13.3 M 6-benzylaminopurine (BA). Shoots were rooted on MS medium with 2.9 M IAA and 1.4 M gibberellic acid (GA3) and the regenerated plants flowered and set seeds normally.  相似文献   

16.
Structural study of fucoidan from Cladosiphon okamuranus tokida   总被引:1,自引:0,他引:1  
A structural study was carried out on a fucoidan isolated from the brown seaweed Cladosiphon okamuranus. The polysaccharide contained fucose, glucuronic acid and sulfate in a molar ratio of about 6.1 : 1.0 : 2.9. The results of Smith degradation showed that this polysaccharide has a linear backbone of 13-linked -fucopyranose with a half sulfate substitution at the 4-positions, and a portion of the fucose residues was O-acetylated. The data obtained from partial acid hydrolysis, a methylation analysis and NMR spectra indicated that the -glucuronic acid residue is linked to the 2-positions of the fucose residues, which were not substituted by a sulfate group. These results indicated that the average structure of this fucoidan is as follows: -[(3Fuc-4(±OSO3-)1–)53[GlcA12]Fuc1–]n–. (Half of each fucose residue was sulfated. One O-acetyl ester was present in every 6 fucose residues.)  相似文献   

17.
Sequence-specific assignment of the methyl groups in large proteins can be obtained from an MQ-(H)CCmHm-TOCSY experiment on uniformly 13C-labeled proteins without deuteration (Yang etal., 2004). Here the procedure is further demonstrated on a uniformly 13C-labeled -chain or -chain of human normal adult hemoglobin (65kDa) in the carbonmonoxy form. In addition, a strategy is presented for assigning protons of methyl-containing residues of uniformly 13C-labeled large proteins, on the basis of prior methyl assignments based on MQ-(H)CCH-TOCSY and H(C)CmHm-TOCSY experiments. Assignment of about 80% of the side-chain resonances of methyl-containing residues of carbonmonoxyhemoglobin has been obtained.  相似文献   

18.
To investigate the function of amylases in the fruit-body formation of an ectomycorrhizal fungus, Lyophyllum shimeji, we purified the extracellular amylase in the medium of this fungus. The purified enzyme was obtained from 1.7l stationary culture filtrate, with 4.2% recovery, and showed a single protein band on SDS-PAGE. The molecular mass was about 25kDa. The enzyme was most active at around 40°C and pH 5.0 and stable over pH 4.5–6.5 for 30min at 37°C. This amylase was remarkably activated by the presence of Ca2+ ion (7.7 times that of the control), but Ba2+ and Ag+ completely inhibited the activity. The amylase readily hydrolyzed the -1,4 glucosidic linkage such as dextrin and amylose A (MW, 2900), converting into glucose, and hydrolyzed the -1,6 glucosidic linkage of isomaltohexaose and amylopectin. However, the enzyme did not hydrolyze the cyclic polysaccharides. On the other hand, when a low molecular mass amylose A was hydrolyzed by this amylase, -anomer glucose was produced. From these results, we concluded that the amylase from L. shimeji seems to be a glucoamylase.  相似文献   

19.
Dhar U  Joshi M 《Plant cell reports》2005,24(4):195-200
A callus induction and in vitro plantlet regeneration system for the endangered state flower of Uttaranchal (Saussurea obvallata) was optimized by studying the influence of explant type (root, hypocotyl, cotyledon and leaf), age and different concentrations of plant growth regulators. Explants from 10 to 15-day-old seedlings showed maximum callus induction. Callus formation and shoot differentiation was initiated on Murashige-Skoog (MS) medium containing 6-benzyladenine (BA) and -naphthalene acetic acid (NAA) in all explant types. The best results were obtained using leaf explants: 100% callusing was achieved in MS medium supplemented with 2.5 M BA and 1.0 M NAA, and 100% differentiation along with a multiplication rate of 12 shoots per explant with a combination of 5.0 M BA and 1.0 M NAA. However, the results reflected the existence of high inter-explant variability in response to growth regulators. In vitro rooting of shoots was achieved at an efficiency of 100% in one-half strength MS medium supplemented with 2.5 M indole-3-butyric acid. Application of this protocol has potential for mass multiplication of the target species in a limited time period.  相似文献   

20.
Excessive oxidative stress is implicated in hepatic fibrogenesis. Extracts of Salvia miltiorrhiza (Sm) have been shown to protect cells against oxidative stress. In this study we investigated the in vitro and in vivo effects of Sm on hepatic fibrosis. A cell line of rat hepatic stellate cells (HSC-T6) was stimulated with transforming growth factor-1 (TGF-1). The inhibitory effects of Sm (50~400 g/ml) on TGF-1-induced -smooth muscle actin (-SMA) secretion and the mRNA expressions of fibrosis-related genes, including -SMA, connective tissue growth factor (CTGF), and tissue inhibitor of metalloproteinase-1 (TIMP-1), were assessed. Fibrosis was induced by dimethylnitrosamine (DMN) administration in rats. DMN-treated rats were randomly assigned to 1 of 4 groups: saline, Sm (20 mg/kg), Sm (100 mg/kg), or silymarin (100 mg/kg), each given by gavage twice daily for 5 weeks starting from the onset of DMN administration. Sm (200 and 400 g/ml) significantly inhibited TGF-1-stimulated -SMA secretion and the mRNA expressions of -SMA, CTGF, and TIMP-1 in HSC-T6 cells. Fibrosis scores of livers from DMN-treated rats with either a low (1.8 ± 0.2) or high (1.8 ± 0.1) dose of Sm, or silymarin (1.4 ± 0.2) were significantly reduced in comparison with DMN-treated rats receiving saline (3.1 ± 0.1). Hepatic collagen contents were also significantly reduced by either Sm or silymarin treatment. The mRNA expression levels of -SMA, TGF-1, and procollagen I were all attenuated in Sm- and silymarin-treated rats. Moreover, levels of plasma aspartate transaminase activities were reduced by Sm and silymarin treatment. In conclusion, our results show that Sm exerted antifibrotic effects in both HSC-T6 cells and in rats with DMN-induced fibrosis.  相似文献   

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