摘要:

Negatively stained preparations of 30 different strains of gram‐negative rods representing 20 different taxa were examined in the electron microscope. Thirteen of the strains studied exhibited twitching and six of the strains exhibited gliding motility. Additionally, non‐twitching substrains of two of the twitching strains and a non‐gliding substrain of one of the gliding strains were examined. A variety of cultural media, preparations for negative staining and negative stains were used. It was found that all strains with twitching motility possessed fimbriae, the diameter of which was approximately 50 Å in all but one strain; the fimbriae of this strain had a diameter of approximately 40 Å. The fimbriae were judged to be of polar origin in all cases where the origin could be determined with certainty. On none of the strains without twitching motility could fimbriae be demonstrated. Only one of the six strains with gliding motility possessed f

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00088.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Almost 1000 strains representing well above 50 different species or groups of gram‐negative bacteria were examined for twitching motility. This kind of motility was mainly found in strictly aerobic cocci and rods (viz. Acinetobacter calcoaceticus, Moraxellaspp.,Neisseria gonorrhoeae, N. meningitidis, Pseudomonasspp., phenon 3 of Thornley that is closely related toAcinetobacter, and marine, yellow‐pigmented rods), but also in the facultativeEikenella corrodensand in anaerobic strains presumptively identified as “Bacteroides corrodens” earlier. Strains of species known to possess polar fimbriae were shown to exhibit twitching motility. None of the strains of species known to possess peritrichously arranged fimbriae exhibited twitching m

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00089.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

By examining medium composition and cultural conditions quantitatively it was possible to define conditions suitable to bring twitching motility about. Such conditions include the use of freshly poured, relatively thick and only slightly dried plates of a dilute medium in which the agar concentration is not too high. Incubation should take place in a humid atmosphere. In fact, everything points to the humidity as a factor of the utmost importance. Using strains ofAcinetobacter calcoaceticus, it was found that a pH value of the medium adjusted to 9.0 enhances twitching motility. Spreading growth was not produced if agarose was applied instead of ordinary agars. Twitching motility was inhibited by a number of different chlorides, potassium nitrate, Tween 80 and sodium taurocholate. Possible interpretations of these observations are discussed.

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00090.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Previously published reports have established a correlation between twitching motility and the possession of polar fimbriae in all cases examined. Twitching motility was shown to be highly dependent on the availability of liquid at the agar surface. In the present paper experiments are reported that establish: 1) the dependence of twitching on the existence of a layer of liquid of a particular thickness, 2) the production of such a liquid layer surrounding areas of growing organisms, and 3) the affinity of twitching bacteria for the air‐water interface. Reasoning from these facts, it is postulated that the demonstrated affinity for the air‐water interface is conferred upon the cells by the polar fimbriae. It is also suggested how the movements might be genera

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00091.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Buffalo pox virus (strain BP 4) has been studied by electron microscopy of sections of infected chorioallantoic membrane cells. The ultrastructure of the virus has been described and compared with the ultrastructure of vaccinia virus. No differences between the two viruses were found. In relation to the ways of release two forms of mature virions have been described. These are probably analogous to the previously described C‐ and M‐form of vacci

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00092.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The aim of the study has been to ascertain whetherMicrotus arvalis(common vole) is strongly susceptible toM. bovisbut resistant toM. tuberculosis, as is the case with other members of the vole family, or whether it is susceptible to both species as demonstrated byRobert Koch.Groups of common voles have been injected subcutaneously or intraperitoneally with varying doses of finely dispersed suspensions of a virulent strain ofM. bovisorM. tuberculosis. M. bovismultiplies strongly in the vole organism and a dose as small as 8 viable units provokes a progressive infection with rapid fatal outcome. Autopsy shows considerable processes at the site of injection and in the lymph glands. Tubercles are observed quite frequently in the lungs, but seldom in the liver, spleen and kidneys. The organs contain a large number of tubercle bacilli, the caseous lymph glands enormous numbers. In contrast, the virulence ofM. tuberculosisis low. None of the doses used, the highest being 6 times 106viable units, provokes progressive infection in the animals injected subcutaneously and only in a few of those injected intraperitoneally. The macroscopical findings are inconsiderable, and it is characteristic of theM. tuberculosisinfection that the lymph glands are seldom enlarged and have become caseous in exceptional cases only. The number of bacteria in the organs is small, except in the few animals in which the infection becomes progressive. The conclusion drawn from the experiment is thatMicrotus arvalisis susceptible toM. bovisbut strongly resistant toM. tuberculosis, and in this respect resembles other members of the vole family examined hitherto.

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00093.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Römer(1903) has demonstrated that white mice injected intraperitoneally with large doses of tubercle bacilli isolated from man survived longer than mice injected with tubercle bacilli isolated from cattle. The blood of the spontaneously dead animals contained large numbers of tubercle bacilli. In the present study, red mice are injected intraperitoneally with 10 mg doses of different species of mycobacteria, and the number of bacilli in the blood is estimated at various intervals within the first 24 hours after the inoculation. The number of bacteria is considerably higher in the blood of mice injected withM. bovisthan in animals givenM. tuberculosisor BCG.M. aviumis found in as large numbers asM. bovis, but, in contrast toM. bovis, M. aviumdisappears rapidly from the blood stream. Supplementary experiments show that red mice injected withM. bovishave a shorter survival time than mice injected withM. tuberculosis, and that the bacteraemia induced byM. bovisinto white mice is clearly less pronounced than in red mice

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00094.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

During the recent decade, 1651 isolates ofStaphylococcus aureusfrom 111 patients with cystic fibrosis have been tested for antibiotic sensitivity and half of the isolates have been phage typed. All the patients were followed in one clinic and the policy of antibiotic treatment was consistent during this period. The results show a dynamic situation where ‘epidemic’ phage types during recent years have been gradually replaced by other types and, during the same period, the prevalence of strains resistant to more than one antibiotic decreased. Multiresistant strains including strains resistant to methicillin were infrequent in these patients. From 23 per cent of the patients, the same strains were repeatedly isolated for more than 1 year despite an apparently successful chemotherapy. Recently isolated strains were found to produce cell‐bound as well as extracellular protein A. Ninety‐one per cent of the strains produced extracellular lipase and only 8 per cent were resistant to mercury chloride. Eighty‐one per cent of the patients produced precipitating antibodies againstS. aureusas judged by crossed immunoelectrophoresis. The investigated properties ofS. aureuswere not significantly correlated with the occurrence of precipitating antibodies against these bacteria. The possible significance of protein A in the pathology of the respiratory tract infection is

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00095.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Polysaccharide C (poly C) has been isolated from two strains ofS. epidermidisand characterized chemically. The results suggest that poly C is a wall N‐acetylglucosaminylglycerol teichoic acid, linked through 1:3‐phosphodiester linkages. One poly C preparation contained only β‐linked N‐acetylglucosamine, the other traces of α‐linked sugar in addition. The degree of substitution of sugar in the poly C preparations from the two strains was about 50 and

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00096.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The antigenic properties of polysaccharide C (poly C) ofS. epidermidisstrongly support the analytical indications that it is an N‐acetylglucosaminylglycerol teichoic acid with 1:3‐phosphodiester linkages. The major antigenic determinant is N‐acetylglucosamine, predominantly present in the β‐configuration. Also anti‐glycerophosphate antibodies are produced, apparently dependent on the degree of glycosylation. Purified poly C was unable to sensitize either normal or tanned sheep erythrocytes for agglutination i

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1975.tb00097.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY