[3] Cauxin has been shown to hydrolyze 3-methylbutanol-cysteinylglycine (3-MBCG) in the urine into felinine which then slowly degrades into the putative, sulfur-containing cat pheromone 3-mercapto-3-methylbutan-1-ol (MMB).
This is likely a result of decreased reliance on felinine, due to the existence of additional, more complex signaling molecules that are present in the urine of larger cats.
[2] Cauxin is also present in the seminal fluid of cats and several other mammals, including sheep, pigs, cattle, rams, boars, rats, and mice.
The role of cauxin as an esterase allows it to hydrolyze specific monoacylglycerols, suggesting that it is involved in lipid transfer and metabolism.
[6] Cauxin protein from feline urine was reported in 2008 to act as a nucleator for struvite crystals, in an in vivo system containing magnesium, ammonium, and phosphate ions.