Korean Journal of Applied Entomology, vol. 45, no. 3, pp. 301-307
A ligniolytic bacterial strain was isolated from the digestive tract of a red dragonfly, Sympetrum depressiusculum. It was identified as a Serratia marcescens HY-5 by 16S rDNA sequence analysis and physiological and biochemical analysis. The isolated strain showed proportional increase of ligninolytic activity to the cell growth in the culture media which include lignin compounds. It showed about 25-45% decomposition of lignin compound by 48 hr incubation especially, showed effective decomposition of monomer lignin compounds, vanillin and guaiacol, and a dimer, dealkaline lignin. PCR amplification of 16S rDNA followed by denaturing gradient gel electrophoresis analysis showed high density of S. marcescens HY-5 in the gut of the S. depressiusculum at both gut samples which collected at different site.