Journal of Pure and Applied MicrobiologyVol. 9 No. 4

Haloalkalophilic Cellulose-Degrading Bacteria Isolated from an Alkaline Saline Soil

Maria Patricia Lopez-Ramirez1, Katia Berenice Sanchez-Lopez1, Yohanna Sarria-Guzman1, Juan Manuel Bello-Lopez1, Veronica Lorena Cano-Garcia1, Victor Manuel Ruiz-Valdiviezo2* and Luc Dendooven1

1Laboratory of Soil Ecology, ABACUS, Cinvestav, Av. I.P.N. 2508 C.P. 07360, M?xico D. F., M?xico. 2Laboratory of Biotechnology, Instituto Tecnol?gico de Tuxtla-Guti?rrez, Tuxtla-Guti?rrez, Chiapas, Mexico.

Received on 10 May 2015 and accepted on 26 July 2015

 

ABSTRACT

Microorganisms that degrade cellulose in extreme environments have an enormous biotechnological potential. Seven cellulolytic microorganisms were isolated from soil of the former lake Texcoco (pH 9.6 and electrolytic conductivity 115 dS m?1) in Ar medium (Congo red agar medium) and the enzyme activity was determined semi-quantitatively by measuring the hydrolysis halo around the colony, which varied from 0.8 to 5.0 cm. Of the seven isolated bacteria, two bacteria showed cellulase activity. Phylogenetic analysis based on the 16S rRNA gene, showed that one isolate was closely related to Cellulomonas bogoriensis with a similarity of 99.7% and the other to Nocardiopsis dassonvillei with 99.69% similarity. The C. bogoriensis strain had a maximum cellulolytic activity of 177 mU ml?1 and the N. dassonvillei strain 136 mU ml?1 at pH 9 and 37 ?C. Celluloytic activity of the two strains isolated from the saline alkaline soil was not reported previously.

Keywords : Actinobacteria, Carboxymethylcellulose (CMC), Cellulases, Extremophiles.