There are a number of ELISA Kits available for the measurement of glutamate-ammonia ligase (glutamine synthetase), another term for the human protein, glutamate-ammonia ligase. Other synonyms may include: glutamine synthetase, cell proliferation-inducing protein 59, glutamate decarboxylase, glutamine synthase, proliferation-inducing protein 43, GLNS, and GS. It is encoded by the GLUL gene to yield a protein 373 amino acids in length and 42.1 kDa in size. The protein is categorized into the Glutamine synthetase family. Versions of glutamate-ammonia ligase (glutamine synthetase) are present in other organisms, including: Mouse, Rat, Arabidopsis, E. coli.