Species-specific distribution of a modular family 19 chitinase gene in Burkholderia gladioli

The chitinase gene chiB of Burkholderia gladioli strain CHB101 is the first family 19 chitinase gene found in bacteria other than Streptomyces. The pr esence of chitinase genes homologous to the chiA (family 18) and chiB (fami ly 19) of R. gladioli strain CHB101 was investigated in closely related spe cies Burkholderia andropogonis, Burkholderia caryophylli. Burkholderia glum ae, Burkholderia plantarii, and Burkholderia cepacia as well as in other st rains of B. gladioli. Twenty-seven of the 30 strains of R gladioli examined produced chitinases and were all positive when probed with chiA and chiB o f CHB101, although the restriction fragment length polymorphism patterns in these strains were not necessarily identical to that of CHB101. The remain ing three strains of R. gladioli and all strains of the other Burkholderia species tested showed no chitinase activity and gave no signal with the chi A or chiB probes. Analysis of the 16S rDNA sequence indicated that the thre e chitinase-negative strains of B. gladioli were phylogenetically closer to B. glumae or B. cepacia than to B. gladioli, and should therefore be reass igned. Apparently, possession of a modular family 19 chitinase gene homolog ous to chiB of CHB101 is a species-specific characteristic of B, gladioli. In this article, we show the species-specific distribution of a family 19 c hitinase gene in B. gladioli. (C) 2001 Federation of European Microbiologic al Societies. Published by Elsevier Science B.V. All rights reserved.