Chapter 4.2, Problem 2R

Summary Introduction

To review:

Whether the presence of thermophilic microorganisms changes the interpretation of results derived from the Pasteur’s swan-neck experiment and the experiments that could be performed to inactivate the thermophiles.

Given:

A classic experiment was performed by Pasteur to disprove the spontaneous generation of the microbes. The experiment was done in swan-necked flask as observed in the following figure:

Figure: Pasteur’s swan-neck experiment

Introduction:

Thermophilic organisms are those, which have a presence of long-chain saturated fatty acids in their membranes that allow them to withstand the high temperatures without cellular disruption. The normal methods of dry or moist heat sterilization can be evaded by these microorganisms. These organisms can resist an attack of heat but they cannot withstand detergent treatment like sodium dodecyl sulfate (SDS) and beta-mercaptoethanol.