摘要:

When strains ofSalmonella typhimuriumunable to utilizemeso‐tartrate were grown for 24 hours in peptone water containing 0.1 or 1 per cent ofmeso‐tartrate, measurements of the optical densities of the cultures were considerably less than those of cultures grown in peptone water withoutmeso‐tartrate. This reduction in the growth yield was observed not only when themeso‐tartrate was present throughout the whole period of incubation, but also when themeso‐tartrate was added to cultures in the log phase of growth, for there was then an immediate reduction in the rate of growth and a reduction in the final population of cells. These effects were observed whether growth was assessed turbidimetrically or by viable count. The effect of themeso‐tartrate was not bactericidal, for washing of the inhibited cells and their transfer to fresh peptone water released them from the inhibited state. Some Krebs cycle intermediates, such as oxaloacetate, malate, fumarate or succinate, when added to peptone water cultures ofmeso‐tartrate‐non‐fermenting strains stimulated their growth and when added together with themeso‐tartrate prevented themeso‐tartrate from exerting its growth inhibitory effect. Other Krebs intermediates, such as citrate, although growth stimulatory, had only a limited effect in releasing cells from the growth inhibition bymeso‐tartrate. Inhibition was also observed in defined salts media in which the presence ofmeso‐tartrate preventedS. typhimuriumstrains frommeso‐tartrate‐negative biotypes from using glycerol or

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02180.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Altogether 94 strains of the so‐called mannitol‐fermenting type ofStr. bovishave been studied. These strains have been found to form a very homogeneous group of streptococci, culturally and biochemically. They differ clearly from theStr. bovisdescribed byOrla‐Jensen.It is suggested that these streptococci should be considered as identical with theStr. faecalis septicusofFrie

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02181.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Treponema cuniculiwas studied in the electron microscope by means of negative staining and ultrathin sectioning techniques. The sectioned organisms were studiedin situin biopsies from lesions of infected skin. Cells ofT. cuniculiwere found to be regular helices 8–15 μm long and 0.15 μm wide. The ends of the cells were pointed and three flagella were inserted in a row subterminally at each end. The flagella wound around the organisms and overlapped in the middle of the treponemes. The fine structure of isolated flagella was similar to that of flagella obtained from other treponemes. Treatment ofT. cuniculiwithMyxobacterAL‐1 protease 1 revealed bundles of intracytoplasmic microtubules. The diameter of each tubule was about 7 nm. In the ultrathin sections of infected tissueT. cuniculiwas observed in intercellular spaces in thestratum spinosumand thestratum basalelayers of the epidermis. No treponemes were observed in the connective tissue of the dermis. Sections of the microorganisms show the same structural pattern as previously described forT. pallidumNichols. The organisms are surrounded by two tripple‐layered membranes with the flagella situated in between. The ultrastructure of the pathogenic treponemes,T. cuniculi, T. pallidumandT. pertenueis c

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02182.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Purified vesicular stomatitis virus, Indiana serotype, disintegrated partly spontaneously in sucrose gradient releasing small haemagglutinin with density of 1.20 g/cm3. Three different structures could be seen in electron micrographs, rosettes, fragments of envelope and pieces of nucleoprotein helix with surface structures. In polyacrylamide gel electrophoresis viral polypeptides 2, 3 and 4 (numbered in order of increasing mobility) were found. Polypeptide 1 was absent or seen only in very small quantities. Routine laboratory procedures such as pelleting, centrifugation in sucrose, freezing and thawing and also storing at +4°C, increased this disintegration. Nonidet P 40 released from viruses structural components, from which the haemagglutinating capacity was reactivated after removal of detergent with ether. This haemagglutinin had a S‐value of 65S on the average, banded in CsCl at a density of 1.24 to 1.27 g/cm3and after purification contained only one viral polypeptide, VP 2, in acrylamide gel electrophoresis. This polypeptide is usually considered to be associated with surface projections. Electron micrographs revealed aggregates of uniform structures, which in size and shape resemble surface projectio

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02183.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

On treatment of a serum positive for Australia antigen, with increasing concentrations of the detergent Tween 80, an advancing disintegration of the Australia antigen particles can be demonstrated. It is noteworthy that the Australia antigen tubules, after having passed a stage of periodical constrictions of approximately 20 nm, eventually disappear completely, while the 20 nm spherical Australia antigen particles remain. The Dane particles (42 nm) showed increasing destruction of their outer, Australia antigen containing membrane, finally releasing a 27 nm particle with “capsomere‐like” structures on its surface. At the highest detergent concentration utilized (0.5 per cent), no particles could be demonstrated in the specimens. The 27 nm particles were aggregated by sera containing no Australia antibodies or antigen, drawn from patients who had previously undergone virus B hepatitis. It is concluded that the 20 nm Australia antigen particles may be a secondary phenomenon produced by a detachment mechanism from the tubules, only the latter being actually produced in connection with virus replic

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02184.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

In cell free extracts fromNeisseria meningitidis2 species of glutamate dehydrogenase are found by agar gel electrophoresis, one NAD‐linked and the other NADP‐linked. The activity of the NAD‐linked enzyme is decreased when glucose is added to the medium, while the activity of the NADP‐linked one is increased by the same conditions. This observation is consistent with the hypothesis that NAD‐linked GDH mainly has a degradative function, while the NADP‐linked one is active in the biosynthesis o

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02185.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

The glutamate dehydrogenase system is examined in differentNeisseriaspecies. The pH optima, temperature sensitivity, and the effect upon enzyme activity by adding glucose to the medium are compared to the findings inN. meningitidis.By agar gel electrophoresis it is shown that all species exceptN. catarrhalis, N. ovisandN. caviaecontain 2 different glutamate dehydrogenases, one linked to NAD and the other one to NADP. The 3 species mentioned possibly contain only one glutamate dehydrogenase, reacting with both coenzymes. The taxonomic implications of these findings are discussed.

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02186.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

ThreeEscherichia colistrains representing strains from faeces and foods were established as antigenic test strains for three newE. coliO groups, O154, O155 and O156. One of the strains, O154, was also designated as K antigen test strain for a newE. coliK antigen, K94.

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02187.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

An indirect immunofluorescence technique was applied to the typing ofHerpesvirus Hominis(HVH) strains of genital and non‐genital origin. The virus type was determined from aceton‐fixed cells with rabbit convalescent sera and anti‐rabbit conjugate. Results from kinetic neutralization confirmed the results. Cytopathic effect and plaque characteristics in Vero and chick embryo cell monolayers were evaluated for their usefullness in distinguishing type 1 strains from type 2 strains. Cytopathic effect was found to be a less reliable marker even under standardized conditions. On the other hand, the plaque size in Vero cells and the plaque forming capacity in chick embryo cell monolayers discriminated the two

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02188.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Experience with serogrouping and pyocine typing ofPseudomonas aeruginosahas been presented. The Habs serogrouping system was compared with the schemas ofHomma et al., ofLányi, and ofSandvik.All the reference strains ofHomma et al.were groupable by the Habs set, likewise most of the Lányi strains. The bovine Sandvik serogroup reference strains all had a Habs counterpart, except O:II which was incorporated in the Habs system as O:13. The bovine serogroup O:VIII corresponded to Habs O:8. It was considered justified to recognize the Wahba O:14 as a separate entity. The pyocine typing method ofGillies&Govanwas suitable since it rendered a reasonably reproducible result. With this procedure, 96.7 per cent of the strains were typed. The major disadvantage of the method was its insufficient subdivision of theP. aeruginosastrains. Only three types constituted 65.3 per cent of the material. The data suggested a correlation between certain serogroups and pyocine type

ISSN:0365-5563    

DOI:10.1111/j.1699-0463.1973.tb02189.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY