PRELIMINARY STUDIES ON UPTAKE OF SULFUR-35 BY ESCHERICHIA COLI

Abstract

Water, a basic need of human beings, is a potential carrier of organisms responsible for diseases. Supply of safe and potable water is the "basic responsibility of a public health engineer. The conventional methods for bacterial quality assessment of water require 48 to 72 hours time for confirmed results and by that time water is distributed to consumers and water borne diseases spread. This fact minimises the utility of the conventional procedures and consequently the need for a rapid test enumerating bacteria. The use of radioisotopes in water quality assessment has reduced the time of test drastically. It has been shown by Khanna(13) that the duration of test time could be reduced to one hour by employing modified coprecipitation technique for multiplying cells using phosphorus-32 as the radiotracer. The study presented herein employs radiotracer sulfur-35. The metabolism of sulfur-35 has been studied to determine if the equilibrium is achieved between this radioisotope and the -bacterial cells in substrates in a shorter duration as compared to phosphorus-32. The efficacy of the technique proposed to reduce the required time, significantly, for enumerating water bacteria has I - been experimentally demonstrated. The determination of the uptake of sulfur by a water sample, estimated for stipulated experimental conditions, promises an absolute utility for enumerating bacteria. Besides the usefulness of evolved technique in controlling (iv) bacteriological quality of public water supplies, their role in civil defence, as a means of detecting bacteriological warfare, be cited on the credit side for their adoption by public health authorities.