Increase in peroxisome number and the gene expression of putative glyoxysomal enzymes in Chlamydomonas cells supplemented with acetate

J Plant Res. 2015 Jan;128(1):177-85. doi: 10.1007/s10265-014-0681-8. Epub 2014 Nov 21.

Abstract

We cultured Chlamydomonas reinhardtii cells in a minimal culture medium supplemented with various concentrations of acetate, fatty acids, ethanol, fatty alcohols, or sucrose. The presence of acetate (0.5 or 1.0%, w/v) was advantageous for cell growth. To determine whether peroxisomes are involved in fatty acid and fatty alcohol metabolism, we investigated the dynamics of peroxisomes, including changes in their number and size, in the presence of acetate, ethanol, and sucrose. The total volume of peroxisomes increased when cells were grown with acetate, but did not change when cells were grown with ethanol or sucrose. We analyzed cell growth on minimal culture medium supplemented with various fatty acids (carbon chain length ranging from one to ten) to investigate which fatty acids are metabolized by C. reinhardtii. Among them, acetate caused the greatest increase in growth when added to minimal culture media. We analyzed the transcript levels of genes encoding putative glyoxysomal enzymes. The transcript levels of genes encoding malate synthase, malate dehydrogenase, isocitrate lyase, and citrate synthase increased when Chlamydomonas cells were grown on minimal culture medium supplemented with acetate. Our results suggest that Chlamydomonas peroxisomes are involved in acetate metabolism via the glyoxylate cycle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates / pharmacology*
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Chlamydomonas / cytology
  • Chlamydomonas / enzymology*
  • Chlamydomonas / genetics*
  • Chlamydomonas / ultrastructure
  • Culture Media / pharmacology
  • Gene Expression Regulation, Plant / drug effects*
  • Genes, Plant
  • Glyoxysomes / drug effects
  • Glyoxysomes / enzymology*
  • Glyoxysomes / genetics
  • Microscopy, Fluorescence
  • Peroxisomes / drug effects
  • Peroxisomes / metabolism*
  • Peroxisomes / ultrastructure
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism

Substances

  • Acetates
  • Culture Media
  • RNA, Messenger