Computational Molecular Bioscience, 2019, 9, 1-12 http://www.scirp.org/journal/cmb ISSN Online: 2165-3453 ISSN Print: 2165-3445 DOI: 10.4236/cmb.2019.91001 Feb. 22, 2019 1 Computational Molecular Bioscience Bacterial Heavy Metal Resistance Genes and Bioremediation Potential Hannah Johnson 1 , Hyuk Cho 2 , Madhusudan Choudhary 3* 1 Advanced Technology Cores, Baylor College of Medicine, Houston, TX, USA 2 Department of Computer Science, Sam Houston State University, Huntsville, TX, USA 3 Department of Biological Sciences, Sam Houston State University, Huntsville, TX, USA Abstract There is a worldwide distribution of heavy metal pollution that can be ma- naged with a bioremediation approach using microorganisms. Several bac- terial species belonging to the Proteobacteria have been shown to tolerate heavy metal stress, including toxic salts of noblemetals. Rhodobacter sphae- roides, a model bacterium has previously been utilized for bioremediation studies. A bioinformatics approach was employed here to identify the distri- bution of genes associated with heavy metal tolerance among the sequenced bacterial genomes currently available on the NCBI database. The distribution of these genes among different groups of bacteria and the Cluster of Ortho- logous Groups (COGs) were further characterized. A total of 170,000 heavy metal related genes were identified across all bacterial species, with a majority of the genes found in Proteobacteria (46%) and Terrabacteria (39%). Analysis of COGs revealed that the majority of heavy metal related genes belong to metabolism (COG 3), including ionic transport, amino acid biosynthesis, and energy production. Keywords Rhodobacter sphaeroides, Heavy Metal Tolerance Genes, Bioremediation 1. Introduction The definition of heavy metals has differed over the years, beginning with defin- ing heavy metals as metals with a density of five times greater than water [1] and then as metals with densities above 4 - 5 g/cm 3 [2] [3]. There are about 30 metals and metalloids within the heavy metals group, including zinc (Zn), mercury (Hg), gold (Au), lead (Pb), cadmium (Cd), copper (Cu), silver (Ag), platinum How to cite this paper: Johnson, H., Cho, H. and Choudhary, M. (2019) Bacterial Heavy Metal Resistance Genes and Biore- mediation Potential. Computational Mole- cular Bioscience, 9, 1-12. https://doi.org/10.4236/cmb.2019.91001 Received: December 22, 2018 Accepted: February 19, 2019 Published: February 22, 2019 Copyright © 2019 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access