The Braun’s lipoprotein (BLP) in Gram-negative bacteria serves to:
Gram negative envelope integrity depends on covalent linkage between outer membrane and peptidoglycan preventing blebbing and leakage. Braun's lipoprotein Lpp 58 amino acid mature after signal peptidase II lipid modification N acyl S diacylglycerol cysteine anchoring into inner leaflet outer membrane plus third acyl chain, most abundant protein about seven times ten to five copies per cell. C terminal lysine forms peptide bond to meso diaminopimelic acid of peptidoglycan tetrapeptide via LD transpeptidases LdtA B C catalyzing attachment post export. Two thirds of Lpp exist bound form linking l
Ref: Braun & Rehn, Annu Rev Microbiol 1969, Braun lipoprotein attaches outer membrane to peptidoglycan.
