Subcellular compartmentation of fructose 2,6-bisphosphate in oat mesophyll cells

✍ Scribed by Manfred Steingraber; William H. Outlaw; Rüdiger Hampp

• Publisher: Springer-Verlag
• Year: 1988
• Tongue: English
• Weight: 540 KB
• Volume: 175
• Category: Article
• ISSN: 0032-0935
• DOI: 10.1007/bf00392428

✦ Synopsis

Evacuolated mesophyll protoplasts from oat (Avena sativa L.) were fractionated by a membrane-filtration technique. This method of rapid quenching of metabolic reactions permitted estimation of the in-vivo pools of fructose 2,6-bisphosphate (Fru2,6bisP) in the cytosol, chloroplasts and mitochondria. Vacuolar Fru2,6bisP was calculated as the difference between control protoplasts and evacuolated ones. The results indicate that Fru2,6bisP is exclusively cytosol-located in oat mesophyll protoplasts. Assuming a cytosolic volume of about 2 pl per evacuolated protoplast, the cytosolic concentration there was 11 μM if protoplasts were in darkness. Illumination of either control or evacuolated protoplasts resulted in a significant decrease in the Fru2,6bisP content within 5 min.