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C WEIBULL

Publications and source records attributed to C WEIBULL.

At least 19 recordsLinked to original sources
PubMed1965

PLASMOLYSIS IN BACILLUS MEGATERIUM.

Weibull, Claes (Central Bacteriological Laboratory of Stockholm City, Stockholm, Sweden). Plasmolysis in Bacillus megaterium. J. Bacteriol. 89:1151-1154. 1965.-Sucrose solutions stronger than 1 m caused plasmolysis in Bacillus megaterium strain M, whereas concentrated NaCl and KNO(3) solutions were ineffective. In plasmolyzed cells, mesosome bodies were found in pockets between the cytoplasmic membrane and the cell wall. After plasmolysis, the cytoplasmic membrane appeared as a triple-layered structure, a "unit membrane." Plasmolysis did not markedly influence the viability of the cells.

Bacillus megaterium↗
PubMed1965

METABOLIC PROPERTIES OF SOME L FORMS DERIVED FROM GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIA.

Weibull Claes (Central Bacteriological Laboratory of Stockholm City, Stockholm, Sweden), and Hans Gyllang. Metabolic properties of some L forms derived from gram-positive and gram-negative bacteria. J. Bacteriol. 89:1443-1447. 1965.-L forms of two gram-positive bacteria, a staphylococcus and a diphtheroid, were found to be devoid of catalase and cytochromes, whereas the normal bacteria from which these L forms were derived contained large amounts of these enzymes. On the other hand, L forms of a gram-negative bacterium, Proteus mirabilis, contained the same cytochromes as normal Proteus bacteria. (Previous investigations showed that normal cells and L forms of P. mirabilis contain approximately the same amounts of catalase.) The respiratory quotients (Q(O2)) of all L forms studied were much lower than those of the corresponding normal bacteria. The conversion of the normal organisms into L forms did not markedly affect their growth rate, measured as the time required for doubling the bacterial mass during the exponential-growth phase.

Bacteria↗
PubMed1963

Morphology of pleuropneumonia-like organisms and bacterial L forms grown in liquid media.

Weibull, C. (Central Bacteriological Laboratory of Stockholm City, Stockholm, Sweden) and Britt-Marie Lundin. Morphology of pleuropneumonia-like organisms and bacterial L forms grown in liquid media. J. Bacteriol. 85:440-445. 1963.-Cells of Mycoplasma hominis, M. laidlawii, and two tissue-culture strains of pleuropneumonia-like organisms (PPLO) moving freely in liquid medium were photographed with an electronic flash as the light source. The photomicrographs thus obtained demonstrated that, in young cultures of high viability, the cells of these organisms were mainly filamentous or, in the case of M. laidlawii, coccoid. In old cultures of the same organisms containing predominantly nonviable cells, granular and vesicular elements were found. By the use of the same photographic technique, liquid cultures of a stable Proteus L form were studied. Although no filaments of uniform thickness were found, there were spherical bodies and some threadlike material connected with the spheres. When samples of PPLO cultures containing filamentous forms were transferred to agar blocks, the filaments were converted to more or less spherical bodies. This conversion could be prevented by fixing the PPLO with formaldehyde. The morphology of Proteus L forms was not noticeably altered by fixation with this reagent.

L Forms↗
PubMed1962

Size and shape of pleuropneumonia-like organisms grown in liquid media.

Weibull, C. (Central Bacteriological Laboratory of Stockholm City, Stockholm, Sweden), and Britt-Marie Lundin. Size and shape of pleuropneumonia-like organisms grown in liquid media. J. Bacteriol. 84:513-519. 1962.-Samples of liquid cultures containing mainly nonaggregated cells of Mycoplasma agalactiae or M. laidlawii were transferred to agar blocks containing the same medium as the liquid cultures. By use of a phase-contrast microscope, photomicrographs were made of the slide cultures immediately after they had been prepared, and the dimensions of a large number of pleuropneumonia-like organisms (PPLO) were measured. These measurements indicated that, in young cultures (incubated for 24 to 48 hr), the size of the cells did not vary much more than that of ordinary bacteria; 95% of the cells had a width of 0.2 to 0.6 mu. The growth of individual PPLO was followed during incubation of the slide cultures. It was found that 80 to 100% of the cells present in liquid overnight cultures divided and gave rise to microcolonies within a few hours. Rod-shaped, ellipsoidal, and spherical cells were seen in these cultures. Liquid cultures incubated for several days contained mainly spherical cells. Fewer than 5% of the cells in these cultures showed any indication of growth during incubation in slide cultures for 5 days. Photomicrographs of cells of M. agalactiae moving freely in liquid medium were taken with an electronic flash as the light source. The photographs thus obtained directly demonstrated the existence of rod-shaped cells.

Agar↗
PubMed1962

Occurrence of catalase in pleuropneumonia-like organisms and bacterial L forms.

Weibull, C. (Central Bacteriological Laboratory of Stockholm City, Stockholm, Sweden) and Kerstin Hammarberg. Occurrence of catalase in pleuropneumonia-like organisms and bacterial L forms. J. Bacteriol. 84:520-525. 1962.-The catalase activity of six pleuropneumonia-like organisms (PPLO), four stable Proteus L forms, and four normal strains of Proteus mirabilis was determined quantitatively. The PPLO (strains of the species Mycoplasma agalactiae, hominis, laidlawii, mycoides, and strains isolated from tissue cultures) exhibited no measurable catalase activity. The L forms decomposed H(2)O(2) approximately ten times as rapidly as the normal bacteria from which they were derived.

Catalase↗