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Bacillus safensis strain VK was isolated from the rhizosphere of a cumin plant growing in the saline desert of Radhanpar, Gujarat, India. Here, we provide the 3.68-Mb draft genome sequence of B. safensis VK, which might provide information about the salt tolerance and genes encoding enzymes for the strain’s plant growth-promoting potential.

During solid-state fermentation of wheat straw, a natural lignocellulosic substrate, the white rot fungus Pleurotus ostreatus produced an extracellular H 2 O 2-requiring Remazol brilliant blue R (RBBR)-decolorizing enzymatic activity along with manganese peroxidase, manganese-independent peroxidase, and phenol oxidase activities. The presence of RBBR was not essential for the production of RBBR-decolorizing enzymatic activity by P. ostreatus, because this activity was also produced in the absence of RBBR. This RBBR-decolorizing enzymatic activity in crude enzyme preparations of 14-and 20-day-old cultures exhibited an apparent K m for RBBR of 31 and 52 M, respectively. The RBBR-decolorizing enzyme activity was maximal in the pH range 3.5 to 4.0. This activity was independent of manganese, and veratryl alcohol had no influence on it. Manganese peroxidase of P. ostreatus did not decolorize RBBR. This H 2 O 2-dependent RBBR-decolorizing enzymatic activity behaved like an oxygenase possessing a catalytic metal center, perhaps heme, because it was inhibited by Na 2 S 2 O 5 , NaCN, NaN 3 , and depletion of dissolved oxygen. Na 2 S 2 O 5 brought an early end to the reaction without interfering with the initial reaction rate of RBBR oxygenase. The activity was also inhibited by cysteine. Concentrations of H 2 O 2 higher than 154 M were observed to be inhibitory as well. Decolorization of RBBR by P. ostreatus is an oxidative process.

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