Involved in the glyoxylate assimilation cycle used to regenerate acetyl-CoA and produce pyruvate as universal precursor for biosynthesis. Catalyzes the cleavage of (R)-citramalyl-CoA to yield acetyl-CoA and pyruvate. (3R)-citramalyl-CoA = acetyl-CoA + pyruvate Divalent cations such as manganese, cobalt, nickel and magnesium. Activated by dithioerythritol (DTE) (in vitro). kcat is 1.7 sec(-1) for lyase activity with (R)-citramalyl-CoA as substrate. Optimum pH is 7 (at 55 degrees Celsius). Optimum temperature is 55 degrees Celsius. Homodimer. Under autotrophic growth conditions. Belongs to the HMG-CoA lyase family.