Positive Selection Determination and Twitching Motility Efficacy on Various Carbohydrates by Caldicellulosirputor bescii

Caldicellulosiruptor bescii is a species of hyperthermophilic, gram-positive bacteria most notable for its ability to hydrolyze plant biomass. It is hypothesised that protein glycosylation plays a role in the ability of C. bescii to attach to plant polysaccharides and form cell-to-cell connections. Recent studies demonstrated the genetic conservation of type IV pili (T4P) and plant biomass deconstruction-related proteins. This project aims to further confirm the conservation by identifying positively selected C. bescii proteins involved in attachment and if they are glycosylated. It will also identify the functional significance of T4P in twitching motility using well-established polysaccharide binding and plating assays. The major pilin PilA was not observed to be glycosylated. The protein sequence analysis suggests an insignificant amount of positive selection of carbohydrate deconstruction-related proteins in the Caldicellulosiruptor genus overall. I also observed a significant increase in colony formation by twitching motility on xylan compared to other carbohydrate treatments. Overall, this knowledge may contribute to our understanding of twitching motility as a whole.