Nitrogen Assimilation in Actinomycetes

Published by: Nepalese Society for Microbiology 

Original Article Nepalese Journal of Microbiology (NJM), 2003, Vol 2, No 1, 2011, pp 61-65)

Nitrogen Assimilation in Actinomycetes

Kiran B Tiwari^1,2* and Upendra Thapa Shrestha^1,2

1Research Laboratory for Biotechnology and Biochemistry (RLABB), Kathmandu, Nepal

2Kantipur College of Medical Science, Sitapaila, Kathmandu, Nepal

Abstract

As actinomycetes are one of the diverse groups of soil bacteria possessing commercially useful enzymes and therapeutically useful bioactive molecules, biochemical characterization of the individual isolates is of utmost importance to understand their basic physiology. The work explored importance and optimization of nitrogen substrates in basal culture media. Besides nitrogen source, actinomycetes can use peptone as carbon source too. However, the growth will be retarded at a concentration above 0.5% of peptone. The organisms can use inorganic nitrogen but growth is pretty slow. Actinomycetes have no essential amino acid; however, organic nitrogen enhances the growth. Actinomycetes are weak acid producers. With 10mM glucose, 0.2% peptone is the optimum concentration for glucose (carbohydrate) utilization test. Hence, carbohydrate utilization test should be done in 0.2% peptone and appreciable lowering of pH should be expected at least with five days of incubation at 28ºC.

Keywords: Actinomycetes, aminoacid, nitrogen assimilation, growth optimization