Molecular characterization of gene encoding halo tolerant amylase of Bacillus paralicheniformis isolated from Jazan region

Abstract

Objectives: This study aims to characterize the gene encoding halo tolerant amylase of bacteria isolated from Jazan region. Materials and Methods: Soil samples were collected from several area of Jazan region, KSA. The samples were serially diluted and plateted on starch agar plates. The amylase producing bacteria were detected by iodine test. To determine the halophilic amylase producing bacteria, several colonies were tested for their ability to grow at higher concentrations of NaCl ranging from 7 to 16%. The bacteria was identified by 16S rRNA and the full length amylase gene was fully identified by sequencing using specific primers. Results: One bacterial halophilic isolate was able to grow on starch agar medium up to 14% NaCl. The Gram stain of the isolate indicated that it is Gram-positive, bacilli. The 16S rRNA gene homology study showed that the bacterial isolate was identified as Bacillus paralicheniformis. Two specific primers were designed named S1F, S1R, to amplify the amylase gene (AMY) region using PCR and the PCR product was sequenced. The sequencing results showed that the full-length amy gene of B. paralicheniformis was of 1452 encoding 483 amino acids. The expected M.Wt. of the protein expressed is of 55 KDa. Conclusion: We report the isolation, identification, and characterization of an isolate of halophilic bacterium isolated from Jazan region. Based on molecular identification, this isolate was identified as Bacillus paralicheniformis. This bacterial strain has an α-amylase gene in its genome and is able to produce extracellular α-amylase. Based on the findings of this work we propose that Bacillus paralicheniformis amy gene could be cloned into expression vector for large scale production.