... mitochondria [15,30,31], and ornithine isexported to the cytosol to be converted into citrulline and arginine [31,32]. In plants, information on thelocalization of citrulline and arginine biosyntheticenzymes ... N-acetylornithinetransaminase; GAT, glutamate N-acetyltransferase; AOD, N-acetyl-ornithine deacetylase; OCT, ornithine carbamoyltransferase; ASS,argininosuccinate synthase and ASL, argininosuccinate ... thermotolerance and insensitivity to inhibition by downstream products, cit-rulline and arginine.ResultsThe enzyme involved in catalysis of the fifth stepof citrulline biosynthesis in wild watermelonleavesDuring...