Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Cycles of mitochondrial energization driven by the ultradian clock in a continuous culture of Saccharomyces cerevisiae.

Lloyd, David, Salgado, L. Eshantha J., Turner, Michael P., Suller, Marc T. E. and Murray, Douglas 2002. Cycles of mitochondrial energization driven by the ultradian clock in a continuous culture of Saccharomyces cerevisiae. Microbiology 148 (11) , pp. 3715-3724. 10.1099/00221287-148-11-3715

Full text not available from this repository.

Abstract

A continuous culture of Saccharomyces cerevisiae IFO 0233, growing with glucose as the major carbon and energy source, shows oscillations of respiration with a period of 48 min. Samples taken at maxima and minima indicate that (i) periodic changes do not occur as a result of carbon depletion, (ii) intrinsic differences in respiratory activity occur in washed organisms and (iii) a respiratory inhibitor accumulates during respiratory oscillations. Plasma membrane and inner mitochondrial membranes generate transmembrane electrochemical potentials; changes in these can be respectively assessed using anionic or cationic fluorophores. Thus flow cytometric analyses indicated that an oxonol dye [DiBAC(4)(3); bis(1,3-dibutylbarbituric acid)trimethine oxonol] was excluded from yeasts to a similar extent (in >98% of the population) at all stages, showing that the plasma membrane potential was maintained at a steady value. However, uptake of Rhodamine 123 was greatest at that phase characterized by a low respiratory rate. Addition of uncouplers of energy conservation [CCCP (m-chlorocarbonylcyanide phenylhydrazone) or S-13(5-chloro-3-t-butyl-2-chloro-4(1)-nitrosalicylanilide)] to the continuous cultures increased the respiration, but had only a transient effect on the period of the oscillation. Electron microscopy showed changes in mitochondrial ultrastructure during the respiratory oscillation. At low respiration the cristae were more clearly defined due to swelling of the matrix; this corresponds to the 'orthodox' conformation. When respiration was high the mitochondrial configuration was 'condensed'. It has been shown previously that a temperature-compensated ultradian clock operates in S. cerevisiae. It is proposed that mitochondria undergo cycles of energization in response to energetic demands driven by this ultradian clock output.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Biosciences
ISSN: 1350-0872
Date of Acceptance: 25 June 2002
Last Modified: 06 Mar 2020 14:00
URI: http://orca.cf.ac.uk/id/eprint/127814

Citation Data

Cited 57 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item