排序方式: 共有10条查询结果,搜索用时 312 毫秒
1
1.
Degradation of lactoferrin by periodontitis-associated bacteria 总被引:1,自引:0,他引:1
Abstract The degradation of human lactoferrin by putative periodontopathogenic bacteria was examined. Fragments of lactoferrin were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and measured by densitometry. The degradation of lactoferrin was more extensive by Porphyromonas gingivalis and Capnocytophaga sputigena , slow by Capnocytophaga ochracea , Actinobacillus actinomycetemcomitans and Prevotella intermedia , and very slow or absent by Prevotella nigrescens , Campylobacter rectus, Campylobacter sputorum, Fusobacterium nucleatum ssp. nucleatum, Capnocytophaga gingivalis, Bacteroides forsythus and Peptostreptococcus micros . All strains of P. gingivalis tested degraded lactoferrin. The degradation was sensitive to protease inhibitors, cystatin C and albumin. The degradation by C. sputigena was not affected by the protease inhibitors and the detected lactoferrin fragments exhibited electrophoretic mobilities similar to those ascribed to deglycosylated forms of lactoferrin. Furthermore a weak or absent reactivity of these fragments with sialic acid-specific lectin suggested that they are desialylated. The present data indicate that certain bacteria colonizing the periodontal pocket can degrade lactoferrin. The presence of other human proteins as specific inhibitors and/or as substrate competitors may counteract this degradation process. 相似文献
2.
E.D. Weinberg 《Biometals》2000,13(1):85-89
Successful microbial pathogens must be adept in obtaining growth-essential iron from healthy hosts. Some potential pathogens, however, are sufficiently impaired in iron acquisition ability so as to be dangerous mainly in hosts with such iron loading conditions as alcoholism, asplenia, hemochromatosis, -thalassemia major, or tobacco smoking. The association of six impaired pathogens (Capnocytophaga canimorsis, Yersinia enterocolitica and Y. pseudotuberculosis, Vibrio vulnificus, Tropheryma whippelii, and Legionella pneumophila) with iron loaded humans is described. 相似文献
3.
Characterization of three strains of Capnocytophaga canis isolated from patients with sepsis 下载免费PDF全文
Michio Suzuki Koichi Imaoka Yumi Haga Masahiro Mohri Ayako Nogami Yoshio Shimojima Yoshimi Irie Satoru Sugimura Shigeru Morikawa 《Microbiology and immunology》2018,62(9):567-573
4.
本文对不同菌株二氧化碳噬纤维菌的全菌蛋白采取SDS-PAGE结合考马斯亮兰染色和银染两种染色方法进行初步研究,结果表明二氧化碳噬纤维菌临床分离株和参考菌株间,各临床分离株间电泳图形存在差异,从牙周炎病人和健康龈下分离的二氧化碳噬纤维菌电泳图形未见有特殊意义的差别,因此本文认为SDS-PAGE可以灵敏地区别二氧化碳噬纤维菌种内菌株间的差异,对种内细菌的进一步分型有一定价值。 相似文献
5.
二氧化碳噬纤维菌属(Capnocytophaga,简称Capno)是国外学者近年从人牙菌斑中分离到的新菌属。作者从人的健康和炎性牙周龈下菌斑中分离到615株Capno,其鉴定特点如下:革兰氏阳性细梭纤柔杆菌,仅在厌氧环境和含10%CO_2的空气中生长;在BHI血琼脂表面形成典型的“润湿性”菌落,并产生桔黄色色素和特殊的焦糖气味;在含葡萄糖的PYG肉汤中最终pH值<6,琥珀酸和乙酸为主要的代谢酸产物。根据发酵碳水化合物和还原硝酸盐可鉴定本菌属的三个种。 相似文献
6.
Purification and characterization of a novel protease from culture filtrates of a Streptomyces sp. 总被引:2,自引:0,他引:2
7.
8.
C. Wyss 《FEMS microbiology letters》1993,108(3):255-258
Abstract Phenylalanine and aspartic acid requirements were determined for 13 species of oral bacteria using the chemically defined medium OMIZ-W1. None of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Eikenella corrodens, Selenomonas sputigene, Treponema pectinovorum, T. socranskii , or Wolinella recta required either of these amino acid constituents of aspartame ( l -aspartyl- l -phenylalanine methylester). Phenylalanine was essential for the growth of Capnocytophaga gingivalis, Eubacterium timidum, Fusobacterium nucleatum, Porphyromonas gingivalis, T. denticola , and T. vincentii , while aspartic acid was not required. With the exception of E. timidum , all phenylalanine-dependent strains could grow when the free amino acid was replaced by aspartame at concentrations at least 10-fold lower than those used for aspartame as an artificial sweetener. 相似文献
9.
Determination of the cell surface hydrophobicity of oral bacteria using a modified hydrocarbon adherence method 总被引:2,自引:0,他引:2
Simon P. Sweet T.Wallace MacFarlane Lakshman P. Samaranayake 《FEMS microbiology letters》1987,48(1-2):159-163
Abstract Hydrophobic interactions between bacterial cell surfaces and colonisable substrates have been implicated in the mechanisms of bacterial adherence. However, current methods of assessing bacterial hydrophobicity as a function of adherence to liquid hydrocarbons (especially hexadecane) do not always produce accurate or reproducible results. Therefore, the present technique was developed using xylene. The hydrophobic surface properties of fresh and type strains of Bacteriodes gingivalis, Bacteriodes intermedius, Capnocytophaga spp., Streptococcus salivarius and Streptococcus sanguis suspended either in saliva ions buffer (SIB) or in saliva diluted in SIB were measured. In SIB the test strains were predominantly hydrophobic. The addition of saliva caused a significant reduction ( P < 0.05) in hydrophobicity compared to SIB alone, with 80% of the strains tested. Since oral bacteria will be suspended in saliva in vivo, it is concluded that bacteria in the oral cavity may be less hydrophobic than previous studies have suggested. 相似文献
10.
Ulrich Z?hringer Simon Ittig Buko Lindner Hermann Moll Ursula Schombel Nicolas Gisch Guy R. Cornelis 《The Journal of biological chemistry》2014,289(34):23963-23976
We here describe the NMR analysis of an intact lipopolysaccharide (LPS, endotoxin) in water with 1,2-dihexanoyl-sn-glycero-3-phosphocholine as detergent. When HPLC-purified rough-type LPS of Capnocytophaga canimorsus was prepared, 13C,15N labeling could be avoided. The intact LPS was analyzed by homonuclear (1H) and heteronuclear (1H,13C, and 1H,31P) correlated one- and two-dimensional NMR techniques as well as by mass spectrometry. It consists of a penta-acylated lipid A with an α-linked phosphoethanolamine attached to C-1 of GlcN (I) in the hybrid backbone, lacking the 4′-phosphate. The hydrophilic core oligosaccharide was found to be a complex hexasaccharide with two mannose (Man) and one each of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo), Gal, GalN, and l-rhamnose residues. Position 4 of Kdo is substituted by phosphoethanolamine, also present in position 6 of the branched ManI residue. This rough-type LPS is exceptional in that all three negative phosphate residues are “masked” by positively charged ethanolamine substituents, leading to an overall zero net charge, which has so far not been observed for any other LPS. In biological assays, the corresponding isolated lipid A was found to be endotoxically almost inactive. By contrast, the intact rough-type LPS described here expressed a 20,000-fold increased endotoxicity, indicating that the core oligosaccharide significantly contributes to the endotoxic potency of the whole rough-type C. canimorsus LPS molecule. Based on these findings, the strict view that lipid A alone represents the toxic center of LPS needs to be reassessed. 相似文献
1