title: Isolation of a chitinolytic Bacillus licheniformis S213 strain exerting a biological control against Phoma medicaginis infection.
abstract: Among nine chitinase-producing strains isolated from Tunisian soil, one isolate called S213 exhibited a potent chitinolytic activity. S213 strain was identified as Bacillus licheniformis by API 50CH system and sequence analysis of its partial 16S ribosomal DNA. Chitinolytic activity was induced either by colloidal chitin or fungal cell walls, and the highest chitinase activity reached at the late stationary phase exhibiting optimal temperature and pH of 50-60 °C and pH 6.0, respectively. SDS-PAGE analysis of the secreted colloidal chitin-induced proteins showed a major protein of about 65 kDa. This protein was identified as chitinase on the basis of its peptide sequences which displayed high homology with chitinase sequence of B. licheniformis ATCC 14580. Moreover, chitinolytic activity containing supernatant inhibited the growth of several phytopathogenic fungi including Phoma medicaginis. Interestingly, S213 strain reduced efficiently the damping-off disease caused by P. medicaginis in Medicago truncatula and should be envisaged in enzyme-based biopesticides against phytopathogen application.
authors: Laboratoire des Substances Bioactives, Centre de Biotechnologie de Borj-Cedria, BP-901, 2050, Hammam-lif, Tunisia.
authors: Imen Ben
authors: IB
authors: Slimene
authors: Olfa
authors: O
authors: Tabbene
authors: Dorra
authors: D
authors: Gharbi
authors: Bacem
authors: B
authors: Mnasri
authors: Jean Marie
authors: JM
authors: Schmitter
authors: Maria-Camino
authors: MC
authors: Urdaci
authors: Ferid
authors: F
authors: Limam
mesh_terms: D000935:Antifungal Agents / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D001203:Ascomycota / Q000187:drug effects* / Q000472:pathogenicity; D001407:Bacillus; D002473:Cell Wall / Q000378:metabolism; D002686:Chitin / Q000737:chemistry / Q000378:metabolism*; D002688:Chitinases / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D003904:Mitosporic Fungi / Q000201:enzymology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D014416:Tunisia
chemical_list: D000935:Antifungal Agents; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D002686:Chitin; D002688:Chitinases