Microbiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Microbiology 143 (1997), 2465-2471
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Arami, S.
Right arrow Articles by Tada, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Arami, S.
Right arrow Articles by Tada, M.
Agricola
Right arrow Articles by Arami, S.
Right arrow Articles by Tada, M.

microbiology, Vol 143, 2465-2471, Copyright © 1997 by Society for General Microbiology

ARTICLES

Reduction of ATPase activity accompanied by photodecomposition of ergosterol by near-UV irradiation in plasma membranes prepared from Saccharomyces cerevisiae

S Arami, M Hada and M Tada
Division of Biological Function and Genetic Resources Science, Faculty of Agriculture, Okayama University, Japan. baiyou-1@cc.okayama-u.ac.jp

When plasma membranes prepared from the yeast Saccharomyces cerevisiae were exposed to near-UV radiation, photodecomposition of ergosterol and reduction of ATPase-activity occurred simultaneously. The Vmax for ATPase activity decreased markedly with increasing near-UV dosage while the Km value remained constant. When ATPase solubilized from the plasma membrane was exposed to near-UV, the activity remained constant irrespective of dosage, indicating that the ATPase molecule itself was not damaged by near-UV irradiation. The relationship between content of ergosterol and ATPase activity was examined using liposomes constructed with lipids extracted from the membrane. Maximum activity of ATPase was seen at 5% ergosterol in liposomes; this activity was 2.5 times greater than that in liposomes without ergosterol. Activity of ATPase bound to liposomes with 5% ergosterol was reduced after near-UV irradiation, while the activity remained unchanged in the case of the liposomes without ergosterol. Fluidity of the liposomes with 5% ergosterol also decreased with increasing near-UV dosage. Dosage-response curves for reduction of ATPase activity and for decrease in fluidity were similar to that for photodecomposition of ergosterol. These results suggested that the reduction of ATPase activity in the membrane by near-UV irradiation was not caused by photochemical degradation of the primary structure of the ATPase molecule, but was attributable to conformational change resulting from an alteration in the higher-order structure of the membrane due to photochemical decomposition of ergosterol.


This article has been cited by other articles:


Home page
 MicrobiologyHome page
M. Berney, H.-U. Weilenmann, and T. Egli
Flow-cytometric study of vital cellular functions in Escherichia coli during solar disinfection (SODIS)
Microbiology, June 1, 2006; 152(6): 1719 - 1729.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL MICROBIOLOGY J GEN VIROL
J MED MICROBIOL ALL SGM JOURNALS
Copyright © 1997 Society for General Microbiology.