Lysophosphatidylserine (LPS) lipase that mediates the hydrolysis of lysophosphatidylserine, a class of signaling lipids that regulates immunological and neurological processes (PubMed:25290914, PubMed:30237167, PubMed:30420694, PubMed:30720278, PubMed:30643283). Represents a major lysophosphatidylserine lipase in the brain, thereby playing a key role in the central nervous system (By similarity). Also able to hydrolyze oxidized phosphatidylserine; oxidized phosphatidylserine is produced in response to severe inflammatory stress and constitutes a proapoptotic 'eat me' signal (PubMed:30643283). Also has monoacylglycerol (MAG) lipase activity: hydrolyzes 2-arachidonoylglycerol (2-AG), thereby acting as a regulator of endocannabinoid signaling pathways (PubMed:22969151, PubMed:24027063). Has a strong preference for very-long-chain lipid substrates; substrate specificity is likely due to improved catalysis and not improved substrate binding (PubMed:30237167). 1-(9Z-octadecenoyl)-sn-glycero-3-phospho-L-serine + H2O = (9Z)-octadecenoate + H(+) + sn-glycero-3-phospho-L-serine 1-(9Z-octadecenoyl)-sn-glycero-3-phospho-(1'-sn-glycerol) + H2O = (9Z)-octadecenoate + H(+) + sn-glycero-3-phospho-(1'-sn-glycerol) 1-(9Z-octadecenoyl)-sn-glycero-3-phospho-(1D-myo-inositol) + H2O = (9Z)-octadecenoate + H(+) + sn-glycero-3-phospho-1D-myo-inositol 1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine + H2O = (9Z)-octadecenoate + H(+) + sn-glycero-3-phosphoethanolamine 1-(9Z-octadecenoyl)-sn-glycero-3-phosphocholine + H2O = 1-(9Z-octadecenoyl)-sn-glycerol + H(+) + phosphocholine 2-(9Z-octadecenoyl)-glycerol + H2O = (9Z)-octadecenoate + glycerol + H(+) 1-hexadecanoyl-sn-glycero-3-phospho-L-serine + H2O = H(+) + hexadecanoate + sn-glycero-3-phospho-L-serine 2-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-glycerol + H2O = (5Z,8Z,11Z,14Z)-eicosatetraenoate + glycerol + H(+) Hydrolyzes glycerol monoesters of long-chain fatty acids. 1-decanoylglycerol + H2O = decanoate + glycerol + H(+) 1-dodecanoylglycerol + H2O = dodecanoate + glycerol + H(+) 1-tetradecanoylglycerol + H2O = glycerol + H(+) + tetradecanoate 2-hexadecanoylglycerol + H2O = glycerol + H(+) + hexadecanoate 1-(9Z-octadecenoyl)-glycerol + H2O = (9Z)-octadecenoate + glycerol + H(+) 2-(9Z,12Z-octadecadienoyl)-glycerol + H2O = (9Z,12Z)-octadecadienoate + glycerol + H(+) 1-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-glycerol + H2O = (5Z,8Z,11Z,14Z)-eicosatetraenoate + glycerol + H(+) 1-(9Z,12Z-octadecadienoyl)-glycerol + H2O = (9Z,12Z)-octadecadienoate + glycerol + H(+) 1-hexadecanoylglycerol + H2O = glycerol + H(+) + hexadecanoate 1-octadecanoylglycerol + H2O = glycerol + H(+) + octadecanoate 1-octadecanoyl-2-(9,10-epoxyoctadecanoyl)-sn-glycero-3-phospho-L-serine + H2O = 1-octadecanoyl-sn-glycero-3-phosphoserine + 9,10-epoxyoctadecanoate + H(+) 1-octadecanoyl-2-(10-hydroxyoctadecanoyl)-sn-glycero-3-phospho-L-serine + H2O = 1-octadecanoyl-sn-glycero-3-phosphoserine + 10-hydroxyoctadecanoate + H(+) 1-hexadecanoyl-2-(10-hydroxyoctadecanoyl)-sn-glycero-3-phospho-L-serine + H2O = 1-hexadecanoyl-sn-glycero-3-phospho-L-serine + 10-hydroxyoctadecanoate + H(+) Selectively inhibited by DO264 (N-3-pyridyl-N'-(1-[3-chloro-4-{2-chloro-4-(trifluoromethoxy)phenoxy}pyridine-2-yl]piperidin-4-yl)thiourea) (PubMed:30420694, PubMed:30720278). Reversibly inhibited by triterpenoids, but with rather low potency (PubMed:24879289). Optimum pH is 7.2-9 with 2-arachidonoyglycerol as substrate. Glycosylated; glycosylation is required for optimal activity. The disease is caused by variants affecting the gene represented in this entry. Belongs to the serine esterase family. A family suffering from Polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract (PHARC) was initially clinically diagnosed with Usher syndrome type 3 (PubMed:22938382). Reexamination of one affected member of this family revealed ataxia but not polyneuropathy, demonstrating the phenotypic heterogeneity in PHARC and the need for careful neurological assessments to distinguish this disease from other neuropathic disorders (PubMed:22938382).