Growth of Staphylococcal L Forms on and Through Membrane Discs of Various Pore Sizes

Molander, C. W.; Weinberger, Howard J.; Kagan, Benjamin M.

doi:10.1128/jb.89.3.907-907.1965

Cited by 12 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This material may be the result of abortive attempts to form colonies. DISCUSSION The present investigation has supported similar findings by other workers that L-phase variants will grow on and pass through Millipore filters of sizes ranging from 1.2 to 0.22 ,um (13,28,34).…”

Section: Resultssupporting

confidence: 92%

“…These results were rather surprising, in view of the fact that this method had been employed by other investigators for determining the size of the smallest reproductive units present in L-phase cultures (13,28). It was assumed that viable elements of the L-phase variant had, in fact, passed through the filters but could not develop into colonies.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Growth of Streptococcal Protoplasts and L-Colonies on Membrane Filters

Wyrick

Gooder

1971

J Bacteriol

View full text Add to dashboard Cite

Membrane filters (Millipore Corp.; pore sizes 1.2 to 0.22 Mm) were placed on the surface of L-phase growth medium solidified with agar. The filter and the surrounding medium were inoculated with either protoplasts or stable broth-grown Lphase variants obtained from Streptococcus faecium strain F24. The L-phase inoculum gave rise to viable L-colonies on the filters and on the medium, whereas protoplasts gave colony formation only on the medium. However, when the Millipore filters were covered by a layer of solid L-phase medium, 75 Mm or greater in depth, before inoculation with protoplasts, colony formation resulted but with atypical morphology. In contrast, inoculation of protoplasts on Nuclepore and Sartorius membrane filters did give rise to L-colonies on the surface and underneath the filters after 2 days of incubation at 37 C. Submicroscopic, viable L-phase elements produced during colony formation were capable of passing through membrane filters with pore channels as small as 0.22 Mrm; these elements required transfer from underneath the filters to fresh agar medium in order to develop into L-phase colonies. Membrane filters were also placed on the surface of L-phase growth medium solidified with gelatin. Inoculation of the filters and surrounding medium with a lysozyme-prepared protoplast suspension gave rise to streptococci on the surface of the filters and on the medium. However, inoculation with the stable broth-grown Lphase variants gave rise to atypical colonies on the medium and only small patches of abortive growth on the filters.

show abstract

Section: Resultssupporting

confidence: 92%

Section: Resultsmentioning

confidence: 99%

Growth of Streptococcal Protoplasts and L-Colonies on Membrane Filters

Wyrick

Gooder

1971

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…Razin (126) has reviewed studies indicating that the plastic mycoplasmas can be squeezed through filter pores smaller than the actual cell size, and Lemcke (77) has recently examined the filtration conditions that allow mycoplasmas to pass through filter pores smaller than the cell diameter. It has also been reported that staphylococcal L-forms with diameters greater than 0.6 lim, when grown on filters, are able to pass through filter-pore sizes as small as 0.05 gm (99). In experiments on A. laidlawii cells, which are 0.5 Am by 2 um, the authors have found (unpublished data) that, with positive pressure (using a Swinney hypodermic adapter), 10% of the titer can be recovered in a 0.45-Mim pore-size filtrate.…”

Section: Introductionmentioning

confidence: 96%

Cell biology of the mycoplasmas.

Maniloff¹,

Morowitz²

1972

Bacteriological Reviews

101

View full text Add to dashboard Cite

“…Besides, coccal forms might still persist among the L colonies as long as they are not stable. The problems, however, are overcome if advantage is taken of the fact that L-forms can pass through filters with a pore size smaller than the one which excludes the coccal forms (2,12). L colonies were therefore filtrated and tested for penicillinase activity immediately after transformation and filtration.…”

Section: Resultsmentioning

confidence: 99%