Studies on carboxymethyl cellulase produced by an alkalothermophilic actinomycete

A novel alkalothermophilic actinomycete having optimum growth at pH 9 and 5 0 degreesC was isolated from self-heating compost from the Barabanki distri ct of Uttar Pradesh, India. Based on its morphology, susceptibility of spor es to heat and novobiocin, guanine-cytosine content of chromosomal DNA and cell wall composition, the organism was classified under Thermomonospora. T he alkalothermophilic actinomycete produced 23 IU/ml carboxymethyl cellulas e (CMCase). The CMCase was purified by fractional ammonium sulphate precipi tation followed by cellulose affinity chromatography and Sephacryl S-200 ge l filtration. The CMCase had a molecular weight of 38 KD and pH of 4.1. The enzyme exhibited optimum activity at pH 5 and temperature 50 degreesC. The CMCase showed pH stability in the range 7-10. The enzyme retained 100% act ivity at 50 degreesC for 72 h and had half-lives of 7 and 3 h at 60 degrees C and 70 degreesC, respectively. The CMCase was stable in the presence of c ommercial detergents such as Ariel, Henko and Surf Excel, indicating its po tential as an additive to laundry detergents. (C) 2001 Elsevier Science Ltd . All rights reserved.