Hydrolyzes odorless N-alpha-acyl-L-glutamine conjugates of short- and medium-chain fatty acids, releasing human axillary malodor compounds (PubMed:12468539, PubMed:18492161, PubMed:17193210). The enzyme is highly specific for the glutamine residue but has a low specificity for the acyl part of the substrate (PubMed:12468539, PubMed:18492161, PubMed:17193210). The two most common products are 3-methyl-2-hexenoic acid (3M2H) and 3-hydroxy-3-methyl-hexanoic acid (HMHA), which are produced from the odorless precursors N-alpha-3-methyl-2-hexenoyl-L-glutamine (3M2H-Gln) and N-alpha-3-hydroxy-3-methylhexanoyl-L-glutamine (HMHA-Gln) (PubMed:12468539, PubMed:18492161, PubMed:17193210). In addition, over 28 different carboxylic acids contributing to human body odor are released by this enzyme from odorless axilla secretions, including several aliphatic 3-hydroxy acids with 4-Me branches, 3,4-unsaturated, 4-Et-branched aliphatic acids, and a variety of degradation products of amino acids (PubMed:17193210). an N(2)-acyl-L-glutamine + H2O = a carboxylate + L-glutamine H2O + N(2)-[(2E)-3-methylhex-2-enoyl]-L-glutaminate = (2E)-3-methylhex-2-enoate + L-glutamine H2O + N(2)-(3-hydroxy-3-methylhexanoyl)-L-glutaminate = 3-hydroxy-3-methylhexanoate + L-glutamine Partial loss of activity with the combination Mn(2+) and chelating agents. Activity is lost in presence of 0.5 mM dithiothreitol. The elucidation of the enzymatic mechanisms of malodor formation may lead to completely new ways to design deodorant actives. A targeted approach to block the enzymatic process offers the possibility of an efficient treatment without perturbation of the resident skin microflora. The enzyme could also be fed with alternative substrates which are designed to release a fragrance note instead of the malodor. Belongs to the peptidase M20 family.