A gene katA that encodes a novel catalase-peroxidase was cloned from the chromosome of Legionella pneumophila. The nucleotide sequence revealed that KatA was highly homologous to members of the bacterial bifunctional catalase-peroxidase family. In addition, KatA has a N-terminal signal sequence and was considered to be present in the periplasm of the bacterium. ß 1999 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. PII: S 0 3 7 8 -1 0 9 7 ( 9 9 ) 0 0 2 5 4 -2