Parachloromercuribenzenesulfonic Acid

Abstract
Vicia faba leaf discs without epidermis were pretreated with parachloromercuribenzenesulfonic acid (PCMBS), rinsed and incubated on [14C]sucrose (1 or 40 millimolar). Those sucrose concentrations were chosen as representative of the apparent uptake system 1 (1 millimolar) and system 2 (40 millimolar) previously characterized. Pretreatment with 0.5 millimolar PCMBS for 20 minutes inhibited system 1 and system 2 by about 70%.