1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase)

1-aminocyclopropane-1-carboxylate (ACC) deaminase is a pyridoxal 5'-phosphate (PLP)-dependent enzyme primarily found in soil-dwelling bacteria and certain fungi (Glick, 2014). Its primary biological function is the degradation of ACC, the immediate precursor to the plant hormone ethylene, into ammonia and alpha-ketobutyrate (Penrose & Glick, 2003). By sequestering and cleaving ACC, the enzyme effectively lowers the concentration of ethylene within plant tissues, which prevents the growth inhibition typically caused by "stress ethylene" during environmental challenges like drought, salinity, or flooding (Glick, 2014). While it is a major target in agricultural biotechnology for the development of plant growth-promoting rhizobacteria (PGPR) and stress-tolerant crops, it is not a therapeutic target in human medicine. There are currently no pharmaceutical drugs that interact with this enzyme, as it is not present in the human genome or associated with human disease pathways (UniProt, 2023). Research in this area is focused on enhancing crop yields and sustainability through microbial inoculation or transgenic expression of the acdS gene.

Other names

ACCD1-aminocyclopropane-1-carboxylic acid deaminaseAcdSACC hydrolase

The enzyme catalyzes the hydrolytic cleavage of 1-aminocyclopropane-1-carboxylic acid (ACC) into ammonia and alpha-ketobutyrate, utilizing pyridoxal 5'-phosphate as a cofactor to reduce the pool of ACC available for ethylene synthesis in plants (Glick, 2014).