Comparison of the cell envelope proteins of Micrococcus cryophilus with those of Neisseria dnd Branhamella species.

In an attempt to elucidate the relation between Micrococcus cryophilus, Neisseria caviae, Neisseria ovis, and Branhamella catarrhalis, fractions derived from outer membranes of a strain of each organism were examined for protein composition by SDS - polyacrylamide gel electrophoresis. Micrococcus cryophilus outer membrane protein showed extensive similarities to that of N. ovis and contained a heat-modifiable protein which behaved almost identically with the corresponding bands previously shown to exist in N. caviae and N. ovis. Branhamella catarrhalis protein was distinctly different from those of M. cryophilus and the two 'false neisserias' N. caviae and N. ovis.     

Genotypic and phenotypic relatedness of 80 strains of Branhamella catarrhalis of worldwide origin

Abstract 80 clinical Branhamella catarrhalis strains of worldwide origin were examined for genotypic relatedness and phenotypic characteristics. Using a quantitative bacterial dot method for DNA-DNA hybridization the strains were found to form a homogeneous group with ΔT_m-values ranging from 0.0–2.3°C. In Minibact-N, an identification kit for oxidase positive, Gram-negative diplococci using eight phenotypic characteristics, all isolates were correctly identified and also demonstrated complete homogeneity except for β-lactamase production. Type strains representing the genera Branhamella, Moraxella and Neisseria were also examined for comparison. B. catarrhalis strain NCTC 4103-known to be atypical-had a ΔT_m-value of 5.7°C and produced γ-glutamylaminopeptidase, in contrast to all other B. catarrhalis strains. In GN MicroPlate^TM, a kit which tests utilizable carbon sources, B. catarrhalis strains were found to be able to utilize up to 16 to 95 carbon sources.     

Lipids of Branhamella catarrhalis and Neisseria gonorrhoeae.

Three strains of Branhamella catarrhalis and three strains of Neisseria gonorrhoeae were analyzed with regard to their phospholipid and neutral lipid composition. B. catarrhalis (ATCC 23246) contained 5.12 +/- 0.34% lipid, determined gravimetrically, compared to 8.56 +/- 0.15% and 9.73 +/- 0.06% for two strains of N. gonorrhoeae. Cardiolipin, phosphatidylglycerol, and phosphatidyl-ethanolamine were identified in extracts of both species. In addition, B. catarrhalis contained small amounts of phosphatidylcholine, and N. gonorrhoeae contained small amounts of lyso-phosphatidylethanolamine, which accumulated with autolysis accompanying late cell culture growth. The kinetics of change of relative amounts of phospholipids in both species were measured and found to differ substantially. Neutral lipid accounted for 30.4% of the total lipid of B. catarrhalis (ATCC 23246) and 7.6% of the total lipid of N. gonorrhoeae NYH 002. Hydrocarbons, triglycerides, free fatty acids, coenzyme Q, diglycerides, and free hydroxy fatty acids were identified in the neutral lipid fraction of both species. The three strains of N. gonorrhoeae, sensitive, intermediate, and resistant to penicillin, exhibited no significant difference in the composition or metabolism of phospholipid.     

Possible presence of a capsule in Branhamella catarrhalis.

Clinical isolates of Branhamella catarrhalis from patients with respiratory infections were used in this study. Electron microscopic observation after treating Branhamella catarrhalis with immune serum and ruthenium red revealed the capsule. In the phagocytosis test, most organisms were not ingested by human polymorphonuclear neutrophils in the presence of normal rabbit serum (NRS), while organisms were primarily cell associated and apparently ingested in the presence of immunized rabbit serum (IRS). The capsule may be one of the virulence factors in this bacteria. This study demonstrates the possible presence of a capsule in Branhamella catarrhalis.     

Antibacterial activity of cefpodoxime against Branhamella catarrhalis.

The antibacterial activity of cefpodoxime against Branhamella catarrhalis was studied. All of the 65 clinical isolates tested were inhibited at and below 1.56 micrograms/ml, both at 10(7) and at 10(5) CFUs. The following was further studied on B. catarrhalis N-5 which showed average susceptibility to each drug examined. Bactericidal activity was observed at and above the MIC. Scanning and transmission electron microscopy revealed morphological changes, such as cellular swelling, bleb formation, inhibition of septum formation, and lysis, of the cells exposed to cefpodoxime at concentrations around the MIC. Cefpodoxime was poorly hydrolyzed by the beta-lactamase and it showed affinity for two penicillin-binding proteins that had approximate molecular weights of 83 and 74 kilodaltons, with I50 values of 3.7 and 2.1 micrograms/ml, respectively.     

Branhamella catarrhalis: epidemiology, surface antigenic structure, and immune response.

Over the past decade, Branhamella catarrhalis has emerged as an important human pathogen. The bacterium is a common cause of otitis media in children and of lower respiratory tract infections in adults with chronic obstructive pulmonary disease. B. catarrhalis is exclusively a human pathogen. It colonizes the respiratory tract of a small proportion of adults and a larger proportion of children. Studies involving restriction enzyme analysis of genomic DNA show that colonization is a dynamic process, with the human host eliminating and acquiring new strains frequently. The surface of B. catarrhalis contains outer membrane proteins, lipooligosaccharide, and pili. The genes which encode several outer membrane proteins have been cloned, and some of these proteins are being studied as potential vaccine antigens. Analysis of the immune response has been limited by the lack of an adequate animal model of B. catarrhalis infection. New information regarding outer membrane structure should guide studies of the human immune response to B. catarrhalis. Immunoassays which specifically detect antibodies to determinants exposed on the bacterial surface will elucidate the most relevant immune response. The recognition of B. catarrhalis as an important human pathogen has stimulated research on the epidemiology and surface structures of the bacterium. Future studies to understand the mechanisms of infection and to elucidate the human immune response to infection hold promise of developing new methods to treat and prevent infections caused by B. catarrhalis.     

Studies on the cellular and free lipopolysaccharides from Branhamella catarrhalis.

Cellular and free lipopolysaccharides obtained from Neisseria catarrhalis and Branhamella catarrhalis were found to be essentially identical. Both cellular and free lipopolysaccharides contained core-oligosaccharides of the following composition: D-glucose (4 mol), D-galactose (1 mol), 2-amino-2-deoxy-D-glucose (1 mol), and 3-deoxy-D-manno-octulosonic acid. Aldoheptose and phosphate components were below levels of detection. Several physical methods indicated that all core-oligosaccharide preparations were identical. Lipid A preparations from cellular and free lipopolysaccharides of both organisms were qualitatively and quantitatively similar; they were composed of decanoic acid, dodecanoic acid, 3-hydroxy dodecanoic acid, 2-amino-2-deoxy-D-glucose, phosphate, and ethanolamine. The results tend to justify the transfer of Neisseria catarrhalis to the genus Branhamella.     

Fimbriation, hemagglutination and adherence properties of fresh clinical isolates of Branhamella catarrhalis.

This study investigated the fimbriation on 24 fresh clinical isolates of Branhamella catarrhalis by electron microscopy. All the strains were isolated from patients with respiratory infections. The Branhamella catarrhalis strains were classified into three groups according to the grade of fimbriation. Among these 24 strains the incidence of densely fimbriated, moderately fimbriated and sparsely fimbriated isolates were 12 (50%), 7 (29%) and 5 (21%), respectively. After five-times serial subculture on Brain Heart Infusion agar, the average number of fimbriae per bacteria was decreased from 174 to 114 in the densely fimbriated strain and from 48 to 10 in the moderately fimbriated strain. Moreover, 20% of the population became non-fimbriated in moderately fimbriated strain after the serial subculture. In strains with higher hemagglutination titer the number of fimbriae was significantly (P < 0.04) more than in strains with lower hemagglutination titer.     

Growth and macromolecular composition of a psychrophile,Micrococcus cryophilus,at elevated temperatures

A psychrophilic bacterium,Micrococcus cryophilus, was found to have a maximum growth temperature of 26 C in glutamate salts minimal medium. Macromolecular composition at various temperatures of incubation is reported. When cultures were transferred to temperatures in excess of maximum for growth, the levels of protein and DNA remained fairly constant, whereas the level of RNA fell drastically. The significance of these findings in relation to thermal injury is discussed.     

Moraxella (Branhamella) catarrhalis: Restriction enzyme analysis typing with HinfI, HaeIII and PstI

Abstract Restriction enzyme analysis typing with Hin fI, Hae III and Pst I was performed on Moraxella (Branhamella) catarrhalis strains consecutively collected from children suspected of respiratory tract infection and the type strain. Use of Hin fI gave the most distinct patterns. Great polymorphism was seen among strains.     

Ultrastructural study on the adherence of Branhamella catarrhalis to oropharyngeal epithelial cell.

In the present study, it was observed that Branhamella catarrhalis adhere to the microplicae of the oropharyngeal epithelial cells. Both long and short microplicae patterns are present on the surface of oropharyngeal epithelial cells and the adherence ability of fimbriated Branhamella catarrhalis also varies according to the microplicae pattern. It was found that Branhamella catarrhalis attached more to one surface of the epithelial cell than to the other, suggesting that the presence of receptors are more on one surface than on the other. Branhamella catarrhalis did not attach to the mucus layer but directly to the epithelial cell surface. Ruthenium red staining specimen showed that Branhamella catarrhalis attached to a granular ruthenium red positive layer on the microplicae and also to a ruthenium red positive component, external to the unit membrane of the epithelial cell membrane.     

一株卡他布朗汉姆菌的重新鉴定

目的对中国医学细菌保藏管理中心库藏的一株卡他布朗汉姆菌CMCC(B)29103株进行重新鉴定。方法用营养琼脂培养基培养CMCC(B)29103株,对其进行形态观察、生理生化特性、脂肪酸组分、分子生物学等多相鉴定,同时与模式株DSM25388T相对照;分析CMCC(B)29103株的特征属性、进化位置以及与Acinetobacter indicus模式株DSM25388T的同源性。结果形态学特性、生理生化以及脂肪酸组分构成均与DSM25388T株十分相似,仅存在个别差异;16 S rRNA基因序列比对显示,CMCC(B)29103株与Acinetobacter(不动杆菌属)相近,与模式株DSM25388T相似性最高,为99.85%。基于Acinetobacter属所有成员的16 S rRNA和rpo B基因的系统进化分析均显示CMCC(B)29103与DSM25388T稳定聚类成一个独立分支,且二者的DNA-DNA同源性为78.3%。结论CMCC(B)29103株属于Acinetobacter indicus种,与模式株DSM25388T为不同的菌株,可将其更名为Acinetobacter i ndicus。     

Expression of Fimbriae and Host Response in Branhamella catarrhalis Respiratory Infections

Sputum during the acute exacerbation of chronic respiratory diseases were observed under the electron microscope, to determine the in vivo expression of surface structures of Branhamella catarrhalis (B. catarrhalis), the polymorphonuclear neutrophil (PMN) response to B. catarrhalis infections, and the composition of sputum. It was found that during infection fimbriae are expressed in B. catarrhalis. However, there were sparsely to densely fimbriated bacteria in each sputum sample. The length of the fimbriae were from 50 to 76 nm. In the sparsely fimbriated B. catarrhalis, external to the cell wall, a thin, granular, electron-dense layer was observed. Due to the presence of fimbriae, this layer was not seen in densely fimbriated B. catarrhalis. Blebs were also found in B. catarrhalis. PMNs were found to phagocytose both B. catarrhalis and debris. Evidence was found that debris were formed mainly by the destruction of PMNs. Bacteria as well as debris were phagocytosed by PMNs.