title: Effects of temperature stress on expression of fimbriae and superoxide dismutase by Porphyromonas gingivalis.
abstract: We examined the biosynthesis of fimbriae and superoxide dismutase (SOD) produced by the periodontopathic bacterium Porphyromonas gingivalis in response to elevated temperature. P. gingivalis 2561, grown at 37 degrees C to mid-logarithmic phase, was subsequently incubated at 39, 41, and 43 degrees C, respectively, to stationary phase. There was no difference in the growth of cells at 37 and 39 degrees C. However, at 39 degrees C there was a 54% reduction in the amount of fimbrillin (fimbriae) as well as decreased expression of mRNA for fimA. On the other hand, under the same conditions, a more than twofold increase in the amount of SOD activity, as well as in the levels of SOD mRNA, was observed. Moreover, cells cultured for 20 h at 39 degrees C showed an 86% decrease of fimbrillin protein and a threefold increase in SOD activity. These observations suggest that P. gingivalis may undergo alterations in its virulence and susceptibility to host immune responses as a result of the elevated temperatures found in inflamed periodontal pockets.
authors.affiliation: Department of Oral Biology, School of Dental Medicine, State University of New York at Buffalo 14214.
authors.forename: A
authors.initials: A
authors.lastname: Amano
authors.forename: A
authors.initials: A
authors.lastname: Sharma
authors.forename: H T
authors.initials: HT
authors.lastname: Sojar
authors.forename: H K
authors.initials: HK
authors.lastname: Kuramitsu
authors.forename: R J
authors.initials: RJ
authors.lastname: Genco
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial; D006360:Heat-Shock Proteins / Q000096:biosynthesis; D016966:Porphyromonas gingivalis / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D013482:Superoxide Dismutase / Q000096:biosynthesis* / Q000235:genetics; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; C063055:fimbrillin; D036781:Fimbriae Proteins; D013482:Superoxide Dismutase