title: Molecular characterization of a fungicidal endoglucanase from the cyanobacterium Calothrix elenkinii.
abstract: A gene responsible for fungicidal activity was identified in the cyanobacterial strain Calothrix elenkinii RPC1, which had shown promise as a biocontrol agent. Functional screening of the genomic library revealed fungicidal (against Pythium aphanidermatum) and endoglucanase activities in two clones. Sequencing revealed an open reading frame of 1,044 bp, encoding 348 amino acid residues with a predicted molecular weight of 38 kDa. Analysis of the deduced amino acid sequence of the putative gene (cael1) showed 99% similarity with the β-1,4-endoglucanase from Anabaena laxa RPAN8 and 97% with the glucanase belonging to the peptidase M20 family of Anabaena variabilis and Nostoc sp. PCC7120, respectively. The putative promoters, ribosomal binding sites and a signal peptide of 22 amino acid residues were identified, revealing the secretory nature of the protein. The phylogenetic tree indicated a close relationship of the gene with Bacillus sp. This study is the first to report on the characterization of an endoglucanase in Calothrix sp.
authors.affiliation: Division of Microbiology, Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Chitra
authors.initials: C
authors.lastname: Natarajan
authors.forename: Vishal
authors.initials: V
authors.lastname: Gupta
authors.forename: Kanika
authors.initials: K
authors.lastname: Kumar
authors.forename: Radha
authors.initials: R
authors.lastname: Prasanna
mesh_terms: D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000737:chemistry / Q000378:metabolism*; D001407:Bacillus / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002480:Cellulase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D000458:Cyanobacteria / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D011775:Pythium / Q000187:drug effects; D017386:Sequence Homology, Amino Acid
chemical_list: D000935:Antifungal Agents; D001426:Bacterial Proteins; D002480:Cellulase