title: Bacillus subtilis chitinase identified by matrix-assisted laser desorption/ionization time-of flight/time of flight mass spectrometry has insecticidal activity against Spodoptera litura Fab.
abstract: An extracellular chitinase was identified and purified (CS1 and CS2) from Bacillus subtilis. The 16S rRNA sequencing was submitted in GenBank (accession numbers KC336487 and KC412256). The purified crude enzymes were identified through matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF MS) analysis. The peptide sequences were matched with chitinase sequences. The peak m/z with 1297. 592 and 3094.570 mascot search resulted sequence was blasted with NCBI protein sequences and confirmed that it is a chitinase enzyme. The effects of chitinase on gut enzymes lactate dehydrogenase, acid phosphatase, alkaline phosphatase and adenosine triphosphatase of the tobacco cutworm Spodoptera litura larvae were investigated. At all concentrations tested, chitinase decreased the activities of these gut enzymes relative to the control. When chitinase treated leaves were fed to larvae in bioassays, gut tissue and gut enzymes were affected. The histological study clearly shows the chitinase treated larval gut, peritrophic membrane and epithelial cells were affected significantly. Chitinase isolated from B. subtilis has effectively reduced the gut enzyme activity and growth of S. litura. The chitin based bioformulation may serve as an effective biocide against the polyphagous pest like S. litura.
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences (SPKCES), Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India; Post Graduate and Research Department of Biotechnology, Selvamm Arts and Science College, Namakkal, Tamil Nadu 637 003, India.
authors.forename: Rajamanickam
authors.initials: R
authors.lastname: Chandrasekaran
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences (SPKCES), Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India.
authors.forename: Kannan
authors.initials: K
authors.lastname: Revathi
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences (SPKCES), Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India.
authors.forename: Annamalai
authors.initials: A
authors.lastname: Thanigaivel
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences (SPKCES), Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India.
authors.forename: Suyambulingam Arunachalam
authors.initials: SA
authors.lastname: Kirubakaran
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences (SPKCES), Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India. Electronic address: senthil@msuniv.ac.in.
authors.forename: Sengottayan
authors.initials: S
authors.lastname: Senthil-Nathan
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D002688:Chitinases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity*; D041981:Gastrointestinal Tract / Q000187:drug effects* / Q000201:enzymology; D019476:Insect Proteins / Q000378:metabolism; D007306:Insecticides / Q000633:toxicity*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D007814:Larva / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development; D008969:Molecular Sequence Data; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D018411:Spodoptera / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development
chemical_list: D019476:Insect Proteins; D007306:Insecticides; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D007770:L-Lactate Dehydrogenase; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D002688:Chitinases; D000251:Adenosine Triphosphatases
keywords: Chitinase; Gut enzymes; Histology; MALDI-TOF MS; Spodoptera litura