title: Production and characterization of N- and C-terminally truncated Mtx2: a mosquitocidal toxin from Bacillus sphaericus.
abstract: Mosquitocidal toxin 2 (Mtx2) is a mosquito-larvicidal protein produced during vegetative stage of Bacillus sphaericus. The toxin consists of 292 amino acids and has a molecular weight of 31.8 kDa. To determine the active core region of the toxin, amino acids at N- and C-termini were sequentially removed. Deletion up to 23 amino acids from the N-terminus (Met1-Tyr23) did not significantly affect protein production and the toxin activity, whereas removal of 26 amino acids from the N-terminus (Met1-Lys26) completely abolished toxicity even though the protein production remained unchanged. Deletion of only 5 amino acids from the C-terminal end yielded the protein that could not be solubilized and rendered the toxin inactive. The results demonstrated that the C-terminal end of Mtx2 is required for proper folding and toxicity. Amino acids at the N-terminus up to Tyr23 did not play a significant role in protein production and toxicity whereas amino acids between Thr24 and Lys26 are required for full toxicity.
authors.affiliation: Department of Biotechnology, Faculty of Science and Technology, Thammasat University, 99 Pahonyothin Road, Klong 1, Klong Luang, Pathumthani, 12120, Thailand.
authors.forename: Kulwadee
authors.initials: K
authors.lastname: Phannachet
authors.forename: Ponlawoot
authors.initials: P
authors.lastname: Raksat
authors.forename: Thidarat
authors.initials: T
authors.lastname: Limvuttegrijeerat
authors.forename: Boonhiang
authors.initials: B
authors.lastname: Promdonkoy
mesh_terms: D000818:Animals; D001407:Bacillus / Q000235:genetics* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism* / Q000633:toxicity*; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism* / Q000633:toxicity*; D009033:Culicidae / Q000187:drug effects; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D017510:Protein Folding; D017384:Sequence Deletion
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; C099210:Mtx2 protein, Bacillus sphaericus; D050505:Mutant Proteins
references.citation: Proc Natl Acad Sci U S A. 1990 Sep;87(17):6659-63
references.pmid: 2204062
references.citation: Appl Environ Microbiol. 2007 Jan;73(1):218-25
references.pmid: 17098916
references.citation: Nat Struct Mol Biol. 2004 Aug;11(8):797-8
references.pmid: 15258571
references.citation: J Bacteriol. 1993 Apr;175(8):2314-20
references.pmid: 8096838
references.citation: Gene. 1985;33(1):103-19
references.pmid: 2985470
references.citation: Gene. 1996 Apr 17;170(1):85-9
references.pmid: 8621095
references.citation: Biotechnol Lett. 2009 Apr;31(4):551-5
references.pmid: 19082531
references.citation: J Bacteriol. 1992 Aug;174(15):5051-6
references.pmid: 1352768
references.citation: Protein Sci. 1995 Mar;4(3):337-60
references.pmid: 7795518
references.citation: J Mol Biol. 2006 Apr 7;357(4):1226-36
references.pmid: 16483607
references.citation: Cell Microbiol. 2003 Mar;5(3):155-64
references.pmid: 12614459
references.citation: Annu Rev Entomol. 1996;41:451-72
references.pmid: 15012337
references.citation: Curr Microbiol. 2004 Aug;49(2):84-8
references.pmid: 15297911
references.citation: Appl Environ Microbiol. 1995 Nov;61(11):4031-6
references.pmid: 8526518
references.citation: FEMS Microbiol Lett. 1993 Feb 1;106(3):275-80
references.pmid: 8384140
references.citation: Microbiol Rev. 1991 Sep;55(3):425-36
references.pmid: 1682792
references.citation: J Mol Biol. 2008 Aug 1;381(1):150-9
references.pmid: 18586267
references.citation: J Bacteriol. 1991 May;173(9):2776-85
references.pmid: 1840581
references.citation: J Biol Chem. 1996 Jun 14;271(24):14183-7
references.pmid: 8662969
references.citation: Nature. 1994 Jan 20;367(6460):292-5
references.pmid: 7510043
references.citation: Microbiol Mol Biol Rev. 1998 Sep;62(3):775-806
references.pmid: 9729609
references.citation: Appl Environ Microbiol. 1996 Jun;62(6):2174-6
references.pmid: 8787415