Isolation and characterization of oxaloacetate decarboxylase ofSalmonella typhimurium, a sodium ion pump

✍ Scribed by Klaus Wifling; Peter Dimroth

• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 658 KB
• Volume: 152
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00425491

✦ Synopsis

Anaerobic growth of Salmonella typhimurium on citrate is Na+-dependent and requires induction of the necessary enzymes during a 20-40 h lag phase. The citrate fermentation pathway involves citrate lyase and oxaloacetate decarboxylase. The decarboxylase is a membranebound, Na+-activated, biotin-containing enzyme that functions as a Na + pump. Oxaloacetate decarboxylase was isolated by affinity chromatography of a Triton X-100 extract of the bacterial membranes on avidin-Sepharose. The enzyme consists of three subunits ~,/~, 7, with apparent molecular weights of 63800, 34500 and 10600. The a-chain contains a covalently attached biotin group and binds to antibodies raised against the ~-subunit of oxaloacetate decarboxylase from Klebsiella pneumoniae. The Na § transport function was reconstituted by incorporation of the purified enzyme into proteoliposomes.