Abstract

CELL WALL COMPOSITION AS AN AID IN THE IDENTIFICATION OF MICRO-ORGANISMS – A STUDY OF SOIL ACTINOMYCETE F-40

P. Ellaiah and V. S. Venkateswara Rao*

ABSTRACT

The actinomycetes are well known as a group of filamentous, Gram-positive bacteria that produce many useful secondary metabolites, including antibiotics and enzymes. A classification of any microbial order is a temporary and man-made arrangement in which similar individuals sharing certain common features are grouped together as taxonomic units at different levels in a taxonomic hierarchy. The success of a classification can be measured by the consistency found when different classes of information are used. Cell wall composition has also become widely accepted as an aid in the identification of genera. In many instances however, the analysis of whole-cell hydrolysates is sufficient for identification. In the present investigation an attempt was made to determine the cell wall composition for selected best isolate (F-40) from 359 actinomycetes isolated from natural substrates. The selected bioactive actinomycete, F-40 was grown in yeast extract- malt extract broth at 28o C for 48 hrs on rotary shaker at 200 rpm. The cells were collected by centrifugation at 4000 rpm for 20 min and washed 3 times with sterile water. Then they were analyzed for amino acids and sugars by chromatographic methods. The results indicates that the cell wall of the strain F-40 contained LL-diaminopimelic acid & glycine with xylose as diagnostic sugar. The above data suggested that the strain F-40 belongs to cell wall type I with sugar pattern C. Further studies are in progress, published and presented elsewhere.

Keywords: Actinomycetes, Gram-positive bacteria, Centrifugation, Chromatography, LL-Diaminopimelic acid, Glycine, Xylose.