Structural Analysis of Halophilic Lipases Isolated from Bledug Kuwu Mud Crater, Purwodadi-Grobogan, Indonesia: A Structural Bioinformatics Study

Abstract

We have cloned lipase genes isolated from six halophilic bacteria isolated from Bledug Kuwu mud crater, Purwodadi-Grobogan, Indonesia. In the present study, we carried out structural bioinformatics analysis to estimate the structural properties of the cloned gene products. In this study, crystal structures of several proteins originated from nonhalophiles, moderate and extreme halophiles were used as references. Moderate and extreme halophilic proteins were grouped into OSMOL and SALT-IN proteins, respectively, which referred to the adaptation strategy of moderate and extreme halophiles against external osmotic pressure exerted by hypersaline solution in their habitats. All structural bioinformatics analysis presented here were carried out by evaluating the relative difference of various analysed parameters between all halophiles proteins including the references and the nonhalophiles ones. Lipase samples from the six Bledug Kuwu bacterial isolates displayed different profiles in amino acid composition, secondary structures, solvent accessible surface areas, radius of gyrations and salt bridges compare to those of all the references structures including OSMOL and SALT-IN proteins. These differences may be correlated to the unique halophiles habitat of all six bacteria isolates, which is the salty mud crater situated at the mainland and far from the sea. Therefore, based on this analysis we can expect that the biochemical and structural property of those six lipase samples were unique as well.