Induction and Characteristics of Staphylococcal L Forms

Abstract

Staphylococcal L forms revealed characteristics not observed previously. The ability to produce coagulase was retained by the variant. In the presence of blood, many L forms were found within red cells, comparable with the intraerythrocytic stages reported for streptococci. Agar lysis was a unique characteristic of the mature L form.Inhibitors were not required to initiate the L stage and the variant and classical form grew commensally on enriched media. As nutrition was simplified, the L stage was supported, whereas the classical form did not reproduce. A small inoculum resulted in exclusive growth of L forms even in media containing special growth factors. The relative ease with which the L forms are produced experimentally suggests that this phase of growth may occur in vivo.

Selection of Media for the Isolation of Common Bacterial L-Phase Organisms from a Clinical Specimen

“…The decreased growth on the BSmedia is now thought to be due to an unidentified inhibitory substance in the lot of Noble agar used. This type of difficulty has been reported previously (19,20) and indicates that all agar used for L-phase growth should be tested for inhibitory effects before using. This factor could also explain the decreased growth in the BS+ and BNa+ plates, although other factors are likely to be involved here also.…”

Immunofluorescence Examination of Typical Staphylococcus aureus Variants and L-forms for Clumping Factor

“…A remnant of cell-wall material may be present on some or all of the so-called L-forms of S. aureus (Pratt, 1966;Hamburger & Carleton, 1966); clumping factor could be a component of this cell-wall remnant. Coagulase and clumping factor are closely associated in the bacterial form of typical S. aweus strains, and L-forms of these strains are known to produce coagulase (Mattman, Turnstall & Rossmoore, 1961).…”

L forms of Staphylococcus aureus

“…This paper reports a study of organisms, derived from cultures of Staphylococcus aureus by exposure to penicillin in the presence of serum and a high concentration of sodium chloride, which are thought to lack the mucopeptide element of the normal cell wall. The production of L forms from staphylococci was described briefly by Dienes & Sharp (1956) and in more detail by Schonfeld (1959, 196l), Marston (1961 a, b ) and Mattman, Tunstall & Rossmoore (1961). The work reported here confirms many of the observations recorded previously and amplifies them with a study of the development of the L colonies and of the sensitivity of the L forms to a wide range of antibiotics; it also provides some additional evidence for the lack of an organized cell wall.…”