Koji Nakayama is Professor of Microbiology and Oral Infection at the Graduate School of Biomedical Sciences, Nagasaki University, Japan. He has published more than 100 papers in international journals including Cell and PNAS.

He received the Kobayashi Rokuzo Memorial Award from the Japanese Society for Bacteriology in 2001 and the Distinguished Scientist Award (Basic Research in Periodontal Disease) from IADR in 2008.

He is one of the pioneers in Molecular Biology in Porphyromonas gingivalis. He cloned P. gingivalis genes encoding superoxide dismutase, RgpB gingipain, etc, and constructed a great number of mutants including double and triple mutants by site-directed mutagenesis and transposon mutagenesis. He found a secretion system, which is now named the type IX secretion system, for gingipains and other virulence factors in P. gingivalis, which is linked to gliding motility of gliding bacteria in the phylum Bacteroidetes. He recently clarified biogenesis of pili named the type V pilus in Bacteroidia class bacteria including P. gingivalis.