Chitin Increases Mycobacterium ulcerans Growth in Acidic Environments.

Species with a chitinous exoskeleton are overrepresented among the aquatic organisms carrying Mycobacterium ulcerans (MU) in nature and laboratory experiments have demonstrated the enhancing effects of chitin on the growth of MU. Field surveys identified pH as one of the key parameters delineating the distribution of MU in tropical regions. The present study investigated the relationship between chitin and pH in MU growth. By focusing on pH variations in the field, our results revealed that chitin enhanced MU growth in acidic environments. The present study provides new information on the ecological conditions favoring the development of this mycobacterium in nature.