Characterization of Bacillus thuringiensis ser. jordanica (serotype H71), a novel serovariety isolated in Jordan.

Abstract

The novel strain of Bacillus thuringiensis J112 isolated from a soil sample in Jordan was classified and characterized in terms of toxicity against dipteran and nematode larvae, crystal protein pattern, plasmid profile, and cry gene content. A new name, Bacillus thuringiensis serovariety jordanica (H serotype 71), is proposed for the reference strain J112. The parasporal crystal proteins were toxic to 3(rd) instar larvae of Drosophila melanogaster and to 2(nd) stage juveniles of root knot nematodes Meloidogyne javanica and M. incognita, but showed poor mosquitocidal activity towards Culex pipiens molestus and Culiseta longiareolata larvae. Solubilized and trypsin-digested crystal proteins possessed moderate hemolytic activity against sheep erythrocytes. SDS-polyacrylamide gel electrophoresis revealed that crystals are composed of several polypeptides ranging from 24 to 170 kDa, of which the 20-, 42-, 140-, and 170-kDa proteins were the major components. Analysis of the plasmid pattern of J112 revealed the presence of two large plasmidic bands of about 160 and 205 kbp. PCR with total DNA from strain J112 and specific primers for cry1, cry2, cry3, cry4, and cyt2A genes revealed that cry1, cry3A, cry4, cry5 and cyt2a genes are present.