Effects of cholesterol and benzyl alcohol on fluorescence transients of pea thylakoids

✍ Scribed by M. Busheva; M. Velitchkova; Tz. Markova; Y. Zanev

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 490 KB
• Volume: 42
• Category: Article
• ISSN: 1011-1344
• DOI: 10.1016/s1011-1344(98)00077-3

✦ Synopsis

Using the chlorophyll fluorescence induction and oxygen ew)lution measurements we investigated the influence of alteration of the fluidity of pea lhylakoid membranes on PSII activity and heterogeneity. The treatment of thylakoid membranes with cholesterol, leading to a decrease of membrane fluidity, resulted in a decrease of the [ale of PSll-mediated electron transport by 311q~ and more pronounced inhibition of PSI photochemical activity. These changes are accompanied by a decrease of PSIIc, centres and a decrease of (lie ratio F,/F,,,, obtained from the chlorophyll fluorescence induction curves. The lluidi;,ation of the thylakoid membranes achieved by incubation of thylakoid membranes with local anaesthetic benzyl alcohol influenced chlorophyll a fluorescence mduclion parameters 1o a smaller extent. The rates of PSI and PSII mediated electron transport are inhibited by 2W,4 after benzyl alcohol Irealment. The level of Qu nonreducing centres seems nol to be altered by either treatment.