Molecular characterization of Bacillus thuringiensis strains from Argentina.
Bacillus thuringiensis INTA 7-3, INTA 51-3, INTA Mo9-5 and INTA Mo14-4 strains were obtained from Argentina and characterized by determination of serotype, toxicity, plasmid composition, insecticidal gene content ( cry and vip ) and the cloning of the single- vip3A gene of the INTA Mo9-5 strain. The serotype analysis identified the serovars tohokuensis and darmstadiensis for the INTA 51-3 and INTA Mo14-4 strains, respectively, whereas the INTA Mo9-5 strain was classified as "autoagglutinated". In contrast to the plasmid patterns of INTA 7-3, INTA 51-3 and INTA Mo9-5 (which were similar to B. thuringiensis HD-1 strain), strain INTA Mo14-4 showed a unique plasmid array. PCR analysis of the four strains revealed the presence of cry genes and vip3A genes. Interestingly, it was found that B. thuringiensis 4Q7 strain, which is a plasmid cured strain, contained vip3A genes indicating the presence of these insecticidal genes in the chromosome. Bioassays towards various lepidopteran species revealed that B. thuringiensis INTA Mo9-5 and INTA 7-3 strains were highly active. In particular, the mean LC(50) obtained against A. gemmatalis larvae with the INTA Mo9-5 and INTA 7-3 strains were 7 (5.7-8.6) and 6.7 (5.6-8.0) ppm, respectively. The INTA Mo14-4 strain was non-toxic and strain INTA 51-3 showed only a weak larvicidal activity.
Franco-Rivera
Alejandro
A
Centro Multidisciplinario de Estudios en Biotecnología-FMVZ, Univ. Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Morelia, Michoacán, México. Apdo. Postal 53, Administración Chapultepec. C.P. 58262, Mexico.
Benintende
Graciela
G
Cozzi
Jorge
J
Baizabal-Aguirre
Victor Manuel
VM
Valdez-Alarcón
Juan José
JJ
López-Meza
Joel Edmundo
JE
D000818:Animals; D001118:Argentina; D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics / Q000633:toxicity; D002876:Chromosomes, Bacterial / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D005798:Genes, Bacterial; D007306:Insecticides / Q000378:metabolism / Q000494:pharmacology; D007814:Larva / Q000254:growth & development / Q000382:microbiology; D007915:Lepidoptera / Q000254:growth & development / Q000382:microbiology; D008969:Molecular Sequence Data; D010572:Pest Control, Biological / Q000379:methods; D010802:Phylogeny; D010957:Plasmids; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D012703:Serotyping
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D007306:Insecticides; C447139:Vip3A protein, Bacillus thuringiensis