Apmis

Holten, Eirik

doi: 10.1111/j.1699-0463.1976.tb01893.xpmid: N/A

The catabolism of glutamate and fumarate was studied by radiorespirometry in selected Neisseria species. The tricarboxylic acid cycle is functioning in all species tested, in spite of the known absence of in vitro malate dehydrogenase activity in N. meningitidis, N. gonorrhoeae and N. cinerea. The results imply a pyridine nucleotide independent oxidation of malate. The oxidation of glutamate is less complete in the presence of phosphate. In N. meningitidis, N. perflava, N. flava, N. subflava and N. lactamica the catabolism of fumarate was slow and incomplete in the absence of glutamate.

Holten, Eirik

doi: 10.1111/j.1699-0463.1976.tb01894.xpmid: N/A

The catabolism of pyruvate and acetate in selected Neisseria species was studied by radio‐respirometry. Both substrates were oxidized via the tricarboxylic acid cycle. N. elongata and the “false neisserias” (N. catarrhalis, N. ovis and N. caviae) did oxidize acetate in the absence of other substrates. This can be explained if it is assumed that these species have glyoxylic acid cycle activity. In the “true neisserias” other than N. elongata, acetate was oxidized only in the presence of glutamate, indicating that these species do not possess a glyoxylic acid cycle.

Holten, Eirik

doi: 10.1111/j.1699-0463.1976.tb01895.xpmid: 814782

In cell free extract from Neisseria meningitidis an enzyme has been found which catalyses the oxidation of L‐malate to oxaloacetate in the absence of pyridine nucleotides, using ferricyanide as electron acceptor. The enzyme was found to be particle‐bound, as determined by sucrose gradient centrifugation. Activity corresponding to this enzyme was demonstrated in extracts from all strains tested of selected Neisseria species. In contrast to the large differences in NAD‐linked malate dehydrogenase activity among the species, the interspecies variation of the pyridine nucleotide independent oxidation of malate was not sufficiently distinct to be useful for classification purposes.

Tufvesson, B.; Johnsson, T.

doi: 10.1111/j.1699-0463.1976.tb01896.xpmid: N/A

In the course of a six‐month‐study of acute gastroenteritis in children of ages up to six years, a reo‐like virus was found in 54 per cent of the faecal specimens obtained at an early stage of the disease, using electron microscopy as screening test. By means of a concentrated complement fixation antigen, composed of a related calf diarrhoea virus cultivated in tissue culture, the rise in titre was found to be significant in 96 per cent of the patients whose faeces contained the reo‐like virus. Antibodies were present in the remaining 4 per cent without rise in titre. In 10 per cent of the cases with gastroenteritis infection was caused by adenovirus or Salmonella. A probable aetiological agent was found in 71 per cent of the patients. It applies to 33 per cent of all cases caused by the reo‐like virus that they were nosocomial infections.

Vesterinen, Ervo

doi: 10.1111/j.1699-0463.1976.tb01897.xpmid: 175640

An in vitro method was used to compare the herpes simplex virus type 2 (HSV2) susceptibility of human ecto‐ and endocervical epithelial cells as well as the induced cellular alterations. HSV2 caused a productive infection and morphological alterations both in ecto‐ and endocervical epithelial cells, but the cytopathogenicity, virus production and development of HSV2 antigens showed a greater sensitivity of ectocervical cells to HSV2 infection. The cytopathogenicity and production of infectious virus did not depend on the antibody pattern of the target cell donor patients. Basically similar morphological alterations were seen in ecto‐ and endocervical cultures and the various morphological types of altered cells are described.

Jyssum, Kaare

doi: 10.1111/j.1699-0463.1976.tb01898.xpmid: 814783

The volume of the whole cell and the fraction of the intact cell bounded by the cytoplasmic membrane (protoplast volume) have been measured by dextran and 14C‐sucrose exclusion spaces in Neisseria meningitidis competence variants. Increase in external osmotic pressure causes contraction of the protoplast volume. Increasing osmolality due to NaCl and MgCl2 also causes contraction of the volume of the whole cell, whereas increasing concentrations of sucrose cause little or no change in the whole cell volume. The experiments demonstrate a significant difference between competent (cp+) and incompetent (cp‐) cells. The cp+ protoplast have a far higher capacity for swelling during decreasing osmolality, and for shrinkage during increasing osmolality. Comparison of spheroplasts obtained by autolysis as well as by the penicillin technique indicates that the average cp+ spheroplast is larger than the average cp‐ one. The significance of the difference in structure of cp+ and cp‐ protoplasts has been discussed.

Jyssum, Kaare

doi: 10.1111/j.1699-0463.1976.tb01899.xpmid: 814784

Transformation efficiency in competent variants of the Neisseria meningitidis Strain M1 increased more than three‐fold after exposure of the recipient cells to approximately 35 atmospheres osmotic pressure for 20 min. Growth of the recipient cells at increased osmotic pressure constantly reduced the transformation efficiency. Exposure of the cells to hypotonic conditions reduced transformability significantly and attempts to restore transformability by means of supernatant solutions from competent cultures were unsuccessful. Incompetent variants of the Strain M1 could not be rendered competent by exposure to increased tonicity. The findings have been discussed in relation to the effects of tonicity variation on N. meningitidis competence variants.

Justesen, Tage; Nielsen, Mogens Lykkegaard

doi: 10.1111/j.1699-0463.1976.tb01900.xpmid: N/A

The effect of evacuation of atmospheric air during transportation on recovery of anaerobicbacteria was investigated. Evacuation of atmospheric air from glass tubes by flushing with pure carbon dioxide lowered the content of oxygen to about 0.4 per cent. Three B. fragilis strains and one strain of Fusobacterium mortiferum and of Peptostreptococcus anaerobius were investigated. Bacterial recovery was determined one hour and 24 hours after evacuation of atmospheric air by pure carbon dioxide and pure nitrogen, and was compared to bacterial recovery from samples transported with free access to atmospheric air. Evacuation by pure carbon dioxide significantly improved the recovery of one B. fragilis strain after 24 hours of transportation and significantly impaired the recovery of Peptostreptococcus anaerobius after one hour of transportation, while evacuation by pure nitrogen significantly improved the recovery of Peptostreptococcus anaerobius after 24 hours of transportation. In all other cases, however, no statistically significant effect on bacterial recovery was found.

Jespersen, Andr.

doi: 10.1111/j.1699-0463.1976.tb01901.xpmid: 814785

The multiplication of bacteria is examined by quantitative culture from the organs of two groups of field voles injected intraperitoneally with a large dose of M. tuberculosis or a small dose of M. bovis and killed at intervals during a period of up to 3 months after the injection. M. tuberculosis given in a dose of 7 times 105 viable units did not multiply, or multiplied only to a small extent. None of the animals in the group died from tuberculosis and the macroscopical lesions found at autopsy were insignificant. In contrast, a dose of 14 viable units of M. bovis provoked generalized tuberculosis running a rapid, fatal course. The bacteria multiplied almost uninhibited throughout the course of the infection.

Oeding, P.; Hájek, V.; Maršálek, E.

doi: 10.1111/j.1699-0463.1976.tb01902.xpmid: 130055

Of 84 Staphylococcus aureus strains isolated from the anterior nares of healthy sheep and from the udders of ewes suffering from purulent mastitis the 89 per cent belonging to the C biotype contained agglutinogen h2 as well as polysaccharide Aβ. Ninety‐five per cent of the C biotype strains were lysed by the bovine phage 78, the human phage set giving only weak reactions at RTD X 100. Two pigment‐negative deficit variants as well as three unclassified strains gave similar results while three A biotype strains and one E biotype strain were definitely different. The close correlation between biochemistry, serology and phage typing substantiates the practical usefulness of the subdivision of S. aureus into biotypes.