Enzyme which catalyzes the acetylation of polyamines (PubMed:15283699, PubMed:16455797, PubMed:17516632). Substrate specificity: norspermidine = spermidine >> spermine > N(1)-acetylspermine (PubMed:17516632). This highly regulated enzyme allows a fine attenuation of the intracellular concentration of polyamines (PubMed:16455797). Also involved in the regulation of polyamine transport out of cells (PubMed:16455797). Also acts on 1,3-diaminopropane and 1,5-diaminopentane (PubMed:16455797, PubMed:17516632). acetyl-CoA + an alkane-alpha,omega-diamine = an N-acetylalkane-alpha,omega-diamine + CoA + H(+) acetyl-CoA + spermidine = CoA + H(+) + N(1)-acetylspermidine acetyl-CoA + spermine = CoA + H(+) + N(1)-acetylspermine kcat is 8.7 sec(-1) with spermidine as substrate (PubMed:15283699). kcat is 5 sec(-1) with spermine as substrate (PubMed:15283699). Optimum pH is 8.0. Amine and polyamine degradation; putrescine degradation; N-acetylputrescine from putrescine: step 1/1. Homodimer. Overexpression of SAT1 and the consequent putrescine accumulation might play a role in the pathogenesis of keratosis follicularis spinulosa decalvans. Belongs to the acetyltransferase family.