protein modification lipoprotein biosynthesis PMID:17071755 PMID:7868582 pathway UPa:UPA00663 GO:0042158 The chemical reactions and pathways resulting in the formation of any conjugated, water-soluble protein in which the nonprotein moiety consists of a lipid or lipids [GO:0042158] Both gram-positive and gram-negative bacteria contain lipoproteins that are a functionally diverse group of surface proteins. The roles assigned to lipoproteins include substrate binding coupled to ABC transport systems, sensing of environmental signals, antibiotic resistance, respiration, germination, conjugation, adherence to and invasion of eukaryotic cells, control of protein secretion and folding, modulation of the immune response, and maintenance of envelope integrity. Upon processing, lipoproteins are ultimately tethered to the membrane via a lipid moiety, diacylglycerol, which is covalently bound to an N-terminal conserved cysteine residue.