Forty-two bacterial strains isolated from marine and terrestrial sources and were tested for agarase productivity. After successive rounds of primary and secondary screening, an agar-degrading marine bacterium from the Red Sea (Hurghada- Egypt), designated R1 attracted our attention by its strong agarovorant and high chitinolytic activity. The morphological, physiological and biochemical characterization showed that the strain was gram negative, facultative anaerobe, motile curved rod, oxidase, catalase urease and O–F test positive. Furthermore, produced acid but no gas from glucose, therefore, it was assigned to the genus Vibrio. Time course of growth, agarase and chitinase production and co-production by Vibrio sp. R1 were determined, Furthermore, the substrate specificity of crude extracellular agarase against different polysaccharides was evaluated. Vibrio sp. R1 crude agarase preparation showed height activity for degrading certain complex polysaccharides other than agar and agarose including shrimp shell colloidal chitine, crab shell chitosan, cellulose, carboxy methyl cellulose, pectin, alginic acid and Arabic Gum. Due to the large number of the hydrolytic enzymes produced by Vibrio sp. R1 and particularly the multi polysaccharides degrading activity of their agarases. We suggest that bacteria play an important ecological role in organic material recycling and mineralization at the edges of the seas and oceans. In addition, the agarase hyperactivity enlightens the potential application of Vibrio sp. R1 as promising new source for possible biotechnological applications
بن عمر شبة | benamar cheba | 15497