Cellular lysis of Streptococcus faecalis induced with triton X-100

Abstract

Lysis of exponential-phase cultures of Streptococcus faecalis ATCC 9790 was induced by exposure to both anionic (sodium dodecyl sulfate) and nonionic (Triton X-100) surfactants. Lysis in response to sodium dodecyl sulfate was effective only over a limited range of concentrations, whereas Triton X-100induced lysis occurred over a broad range of surfactant concentrations. The data presented indicate that the bacteriolytic response of growing cells to Triton X-100: (i) was related to the ratio of surfactant to cells and not the surfactant concentration per se; (ii) required the expression of the cellular autolytic enzyme system; and (iii) was most likely due to an effect of the surfactant on components of the autolytic system that are associated with the cytoplasmic membrane. The possibility that Triton X-100 may induce cellular lysis by releasing a lipid inhibitor of the cellular autolytic enzyme is discussed.

LytR-CpsA-Psr proteins in Staphylococcus aureus display partial functional redundancy and the deletion of all three severely impairs septum placement and cell separation

“…Cells were harvested at OD 600 nm 1.0, washed once with 0.9% NaCl and resuspended in 0.03 M phosphate buffer (pH 6.8) to an OD 600 nm 0.7. Triton X-100 was added to a final concentration of 0.05% to stimulate autolysis (Höltje & Tomasz, 1975;Cornett & Shockman, 1978). The cells were then incubated at 37 1C and 180 r.p.m.…”

The death and lysis of microorganisms in environmental processes

“…The cell wall is the target of many antibiotics, but compounds like EDTA, lysozyme, phenol, and chlorine are also known to act at the outer boundary of the cell [187] together with various surfactants such as Triton X-100 [188], Similarly, the cell membrane succumbs easily to attack by agents capable of disorganizing the structure, or changing specific activities towards ions, or by inhibiting the membrane-bound proteins involved in transport processes such as by the action of some antibiotics [189], or at superoptimal temperatures or with strong oxidising agents. The membrane is also susceptable to attack by agents capable of uncoupling oxidative phosphorylation reactions.…”

Effects of temperature on the autolytic enzyme system of Streptococcus faecalis

“…This incidental observation will be discussed in greater detail elsewhere (E. T. Hinks and L. Daneo-Moore, manuscript in preparation). DISCUSSION A number of observations support the view that in a general way the lytic response observed when cultures are exposed to Triton X-100 is a function of the autolytic enzyme present in the cells and is independent of any effect of the detergent on the protoplast membrane (6). Presumably, the increased rates of lysis observed with increasing detergent concentrations between 0.25 and 1.0 mg/mg of cells (dry weight) ( Table 1) are due to increased penetration of the detergent through the cell wall.…”

“…First, soluble enzyme can be isolated and assayed by using the isolated walls as a substrate (17). Second, various intact cell autolysis assays can be designed by using washed exponential-phase cells suspended in appropriate buffers (10,12,14) where the firstorder rate constant for turbidity loss is assumed to represent the amount of autolytic enzyme activity (6,14). Third, growing exponentialphase cells will lyse under a variety of conditions, including removal of a cell wall precursor (16), additions of a variety of antibiotics such as cycloserine (15), or addition of detergents (6).…”