Abstract

The linkage between the severity of Mycobacterium ulcerans infection and mycolactone polyketide synthase A has been strongly correlated with the presence of sigma factors but recent updates in the field of mycobacteriology are now linking such regulation to the presence of nutrient stimulants and hence spurring parallel reports. This study was therefore aimed at providing a bioinformatic insight into the understanding of factors controlling the expression of this mycolactone polyketide synthase A. Results obtained connote that eleven (11) and fourteen (14) of the isolate’s mycolactone polyketide synthase A are controlled by Sig A and Sig D factors respectively as shown by the presence of those transcriptional binding motifs while nine (9) and six (6) of the isolates lack Sig A and Sig D factors respectively. Two of the isolates mycolactone polyketide synthase A were found to be controlled by neither Sig A nor Sig D factor. When the association between sigma factor, protein structure and the mycolactone polyketide synthase A fragments expression was evaluated, no significant statistical association was found despite the fact that larger number of isolates were controlled by Sig D and bias toward random coil than any other protein structures. The nucleotide substitution favours guanine (60%) than cytosine (40%) and provide evidence that where the percentage of alpha helix is at equilibrium with that of random coil, the substitution rate of guanine and cytosine were also at equilibrium. The transition/transversion bias ratio, the maximum likelihood for the computation and the tajimas neutrality test were estimated to be 0.40, -8864.235 and 8 respectively. Results of this study have shown that even though both Sig A and Sig D factors play important role in mycolactone polyketide synthase A control, other factors beyond these factors are involved.