Molecular insights into the mechanism of thermal stability of actinomycete mannanase. Issue 17 (23rd August 2016)

• Record Type: Journal Article
• Authors: Kumagai, Yuya; Uraji, Misugi; Wan, Kun; Okuyama, Masayuki; Kimura, Atsuo; Hatanaka, Tadashi
• Is Part Of: FEBS letters. Volume 590:Issue 17(2016)
• Page Start: 2862
• Page End: 2869
• Publication Date: 2016-08-23
• Subjects: actinomycete -- glycoside hydrolase family 5 -- mannanase; Biochemistry -- Periodicals; Biophysics -- Periodicals; Molecular biology -- Periodicals; Biochimie -- Périodiques; Biochemistry; Biophysics; Molecular biology; Periodicals; 572.05
• DOI: 10.1002/1873-3468.12322
• Languages: English
• ISSNs: 0014-5793

Abstract

Abstract : Streptomyces thermolilacinus mannanase (StMan), which requires Ca 2+ for its enhanced thermal stability and hydrolysis activity, possesses two Ca 2+ ‐binding sites in loop6 and loop7. We evaluated the function of the Ca 2+ ‐binding site in loop7 and the hydrogen bond between residues Ser247 in loop6 and Asp279 in loop7. The Ca 2+ ‐binding in loop7 was involved only in thermal stability. Mutations of Ser247 or Asp279 retained the Ca 2+ ‐binding ability; however, mutants showed less thermal stability than StMan. Phylogenetic analysis indicated that most glycoside hydrolase family 5 subfamily 8 mannanases could be stabilized by Ca 2+ ; however, the mechanism of StMan thermal stability was found to be quite specific in some actinomycete mannanases. Abstract :