Effect of different stimuli on twitching behavior of endophytic bacteria isolated from Loranthus sp. Jacq.

Bacteria need to adopt to different behavioral tuning depending on the dynamic eco-physiological conditions they are exposed to. One of these adaptive strategies is the use of motility. Here we report the twitching motility response of four endophytic isolates of Bacillus sp. when exposed to different eco-physiological stimuli like different nutrient sources, and mechanical and chemical antagonists on solid surfaces. These endophytic bacteria were isolated from different parts of a hemiparasite Loranthus sp. Jacq. (Loranthaceae) growing on economically important mango trees. The results show that the twitching motility of these bacteria was more when exposed to organic acids, metals salts (among nutrients) and mechanical shearing (stress) than the other factors. Their motility is not affected by surface lubrication or EPS production, but instead is influenced by shear-sensitive structures and affinity to metal ions. Further molecular studies are needed to elucidate the basis of this twitching behaviour on solid surfaces.