Related Experiment Video
Updated: Aug 29, 2026

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae
Published on: March 10, 2012
Cystamine transport in spheroplasts of Saccharomyces cerevisiae
R Ravera1, P Allegra, S Colombatto
1Dipartimento di Medicina e Oncologia Sperimentale, Sezione di Biochimica, Università degli Studi di Torino, 10126 Torino, Italy.
Abstract:
This work is the first demonstration that cystamine is actively accumulated in spheroplasts of Saccharomyces cerevisiae. We have identified and quantitatively determined the transported cystamine in extracts of spheroplasts that have been incubated over different time periods and in the presence of different amounts of cystamine. The method used, already reported in literature for the identification of natural aliphatic polyamines in biological fluids, consists of a derivatization of spheroplast extracts with dabsyl-chloride and subsequent chromatographic analysis in HPLC. Our results show that cystamine accumulation is a function of time, it increases up to 2.5 min then decreases. Transport is inhibited by natural aliphatic polyamines, which, at the same concentration of cystamine (1 mM), cause a decrease in cystamine transport of about 90% for spermidine, 50% for spermine and only 15% for putrescine. Furthermore, transport is energy-dependent as demonstrated by a significant decrease observed in the presence of 2,4-dinitrophenol, ouabain and vanadate. In particular 0.2 mM ouabain causes a decrease of more than 60% in cystamine transport. Our data suggest that cystamine is transported in Saccharomyces cerevisiae spheroplasts via the same polyamine transport system(s) known to be operating in higher eukaryotic cells.
Related Concept Videos
ABC Transporters: Importer
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types:
Transcellular Transport of Solutes
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Overview of Protein Sorting and Transport
Protein sorting can be of two types: signal-based sorting and vesicle-based trafficking. In signal-based sorting, specific amino acid sequences called sorting signals target proteins to the proper location inside the cell either via gated transport or by protein translocation. In gated transport, folded...
Protein Transport to the Stroma
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...
Transport Across the Golgi

