Adp1 Week 8 Lab Report

Genomic Recombination and Deletions in Acinetobactor baylyi ADP1

Shivani Patel

Fall 2015 BIO 493

Introduction: Gene duplication and amplification is a process by which genetic diversity can be created and selected for. Through the understanding of gene duplication and amplification, scientists can garner insight on medical conditions associated with this phenomenon (Seaton et al. 2012). Not only can gene duplication and amplification increase genetic diversity, it can also increase the fitness of bacteria by allowing an increased production of essential nutrients or a gene to gain a new function (Dhar et al. 2014). However, gene amplification is not the only large genome change that can occur in organisms. Large-scale deletions can occur in the genome of certain bacteria. In Salmonella enterica, scientists found that more genome deletions occurred when the mismatch repair mechanism was mutated (Nilsson et al. 2005). Deleting parts of the genome can result in changes in the organism’s fitness (Nilsson et al. 2005). These two processes affecting the genome are tied to increased fitness.

Furthermore, Acinetobactor baylyi ADP1 like most organisms undergoes a process known as DNA recombination, where two complementary DNA strands cross and exchange portions of DNA. During recombination, a structure known as a Holliday Junction forms and must be resolved, completing the exchange of DNA (Aravind et al. 2000). Recombination is a crucial mechanism in both gene amplification and deletion. Specifically, ADP1 contains a protein called YqgF, a putative Holliday Junction Resolvase, due to its structural similarity to a known resolvase named RuvC (Aravind et al.