Chitinases produced by Paenibacillus illinoisensis and Bacillus thuringiensis subsp. pakistani degrade Nod factor from Bradyrhizobium japonicum.
Chitinases are enzymes that hydrolyze internal beta-1,4-N-acetyl-D-glucosamine linkages of chitin. Since the backbone of Nod factors is a chitin oligomer, we investigated whether chitinases produced by soil bacteria Paenibacillus illinoisensis KJA-424 and Bacillus thuringiensis subsp. Pakistani HD 395 are able to degrade Nod factor produced by Bradyrhizobium japonicum, a phenomenon that could disrupt B. japonicum-soybean signaling and nodule establishment when chitinases are present. Purified Nod factor [LCO Nod Bj-V (C(18:1), MeFuc)] was isolated from Bradyrhizobium japonicum and incubated with crude chitinases isolated from KJA-424 and HD395, with or without acetate buffer. After 15 h of incubation, Nod factor in the resulting solution was quantified by HPLC. Degradation was greatest following treatment with KJA-424 (91.9%) and HD395 (86.5%) chitinases in acetate buffer. Treatments that included acetate buffer had higher levels of degradation than those without. For all treatments degradation was greater than 77%.
Jung
Woo-Jin
WJ
Department of Plant Science, McGill University, Macdonald Campus, St Anne-de-Bellevue, QC, Canada.
Mabood
Fazli
F
Souleimanov
Alfred
A
Park
Ro-Dong
RD
Smith
Donald L
DL
D000085:Acetates / Q000378:metabolism; D002021:Buffers; D002688:Chitinases / Q000302:isolation & purification / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D006094:Gram-Positive Bacteria / Q000201:enzymology*; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000378:metabolism*
D000085:Acetates; D002021:Buffers; D008070:Lipopolysaccharides; C091899:Nod factor V, Bradyrhizobium japonicum; D002688:Chitinases