title: High-temperature sorbose fermentation with thermotolerant Gluconobacter frateurii CHM43 and its mutant strain adapted to higher temperature.
abstract: We succeeded in obtaining a strain adapted to higher temperature from a thermotolerant strain, Gluconobacter frateurii CHM43, for sorbose fermentation. The adapted strain showed higher growth and L-sorbose production than original CHM43 strain at higher temperature around 38.5-40 °C. It was also shown to be useful even with the fermentation without temperature control. To understand the sorbose fermentation ability of the adapted strain at higher temperature, D-sorbitol-oxidizing respiratory chain was compared with the CHM43 strain and the adapted strain. We found that the activity of pyrroloquinoline quinone (PQQ)-dependent glycerol dehydrogenase (GLDH), which is a primary dehydrogenase of the respiratory chain and responsible for L-sorbose production, was decreased when the temperature increased, but the decreased activity of GLDH was recovered by the addition of PQQ. Since the adapted strain was found to produce more PQQ than the CHM43 strain, it was suggested that the adapted strain keeps GLDH as holoenzyme with the increased PQQ production, and thus produces more L-sorbose and grows better under higher temperature.
authors.affiliation: Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi 753-8515, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Hattori
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Yakushi
authors.forename: Minenosuke
authors.initials: M
authors.lastname: Matsutani
authors.forename: Duantip
authors.initials: D
authors.lastname: Moonmangmee
authors.forename: Hirohide
authors.initials: H
authors.lastname: Toyama
authors.forename: Osao
authors.initials: O
authors.lastname: Adachi
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Matsushita
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D015964:Gene Expression Regulation, Bacterial; D020576:Gluconobacter / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D006358:Hot Temperature; D009154:Mutation; D045542:PQQ Cofactor / Q000378:metabolism; D013013:Sorbose / Q000378:metabolism*; D013401:Sugar Alcohol Dehydrogenases / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D045542:PQQ Cofactor; D013401:Sugar Alcohol Dehydrogenases; C020672:glycerol dehydrogenase; D013013:Sorbose