'campylobacter jejuni' is a gram-negative microaerophilic bacterium that is widely believed to be the number one cause of food borne gastroenteritis and diarrhea caused by bacteria. the ability to form biofilms may provide protection from oxygen by increasing the expression of genes responsible for oxidative stress protection. the genes that were tested were the ' alkyl hydroperoxide reductase c (ahpc), ferrodoxin (fdxa), catalyse (kata) ', and 'super oxide dismutase (sodb) genes, 16s rrna' and 'gyrase (gyra) genes'. when 'c. jejuni' planktonic and biofilms cells were tested in microaerobic conditions there was no statistically significant differences in the expression of ' ahpc (p=0.139), kata (p=0.065), or sodb (p=0.136). there were differences mfdxafdxa (p=0.008), gyra (p=0.048), and 16s rrna (p=0.002). two methods of qrt-pcr were tested; there was no statistically significant difference between using an abi prism 7000, or the cepheid smart cycler (p=0.776). there were also no differences between the use of either a one-tube or two tube rt-pcr protocol (p=0.388). differences were found in the ahpc (p=0.007), fdxafdxa (p<0.001), and sodb (p<0.001) genes of c. jejuni when grown in aerobic or microaerobic biofilms.