Potential causative agents of biofilm-induced Cholera: an in vitro approach

Abstract

Cholera, while easily treatable, is extremely common across many parts of the world, especially in the regions close to water bodies. The bacteria responsible, Vibrio cholerae, has an interesting affinity to forming biofilms, as well as a seasonal pattern of epidemics. Despite only having two serogroups considered virulent among 200, this disease still has a global estimate of 1.3-4 million cases each year. Various studies point toward the presence of extracellular DNA, as well as the cyclic variation of bacteriophage prevalence against planktonic bacteria as causative agents towards biofilm formation. This research aims to link both of these factors together as a causative agent, and determine how it may play out within the environment as well. Compiling a set of four experiments, this study aims to point out the effect of bacterial growth under Free whole genome DNA, free fragmented genome DNA, phage soup, co-culture, as well as fresh water samples retrieved at different times of the year. For the experiments that involve the author, among an initial 15 strains chosen, 3 best strains, and one optional strain was chosen based on their species, growth factor, as well as susceptibility to bacteriophages. Upon conducting the necessary tests on these bacterial strains, it was observed that there is a directly proportional correlation of biofilm growth relative to the DNA present within the solution, regardless of the source, strain or type of the DNA. This proves that DNA extracted through the phage-mediated lysis of planktonic bacteria can also have a significant effect on the formation of biofilms.