Lipid intermediates in the biosynthesis of the linkage unit between teichoic acids and peptidoglycan

Biosynthesis of the linkage unit joining peptidoglycan to poly(N‐acetylglucosamine 1‐phosphate) in walls ofMicrococcus varians ATCC 29750

“…CDP-glycerol, CDP-[2-3H]glycerol and [/3-32p]CDPglycerol were prepared as in [6,15,16]. [/3-aZP]CDP-[2-all]glycerol was prepared by mixing appropriate amounts of the singly-labelled substrates to give an isotopic ratio (3H : a2p) of about 4:1.…”

“…This doublylabelled material was repurified by paper chromatography [16] and assayed immediately before use. Cells of Micrococcus varians ATCC 29750 were grown and membranes prepared therefrom as in [6,17]. Incubation conditions, paper chromatography, electrophoresis, acid and alkaline hydrolysis, treatment with alkaline phosphatase and measurement of radioactivity were as in [6], Chromatography of products was carried out on a column (1,6 × 50 cm) of Sephadex G-50 eluted with pyridinium acetate (25 mM, pH 6.5) at 40 ml/h flow rate, collecting 4 ml fractions.…”

“…This polymer, like the teichoic acids of several other Gram-positive bacteria, is joined to muramic acid in the peptidoglycan via an oligomer consisting of Nacetylglucosamine phosphate and 3 glycerol phosphate residues [2][3][4][5]. This linkage unit is synthesized from UDP-N-acetylglucosamine (UDP-GlcNAc) and CDP-glycerol through a series of intermediates containing polyprenyl phosphate [6][7][8]. The first step in the synthesis of the linkage unit is the formation of polyprenyl pyrophosphate N-acetylglucosamine, and this is inhibited by the antibiotic tunicamycin [9][10][11][12][13].…”

“…The first step in the synthesis of the linkage unit is the formation of polyprenyl pyrophosphate N-acetylglucosamine, and this is inhibited by the antibiotic tunicamycin [9][10][11][12][13]. Sequential addition of glycerol phosphate residues from CDP-glycerol leads to the synthesis by membrane preparations from Staphylococcus aureus H and M. varians of two further lipids, containing respectively 1 and 2 glycerol phosphates, which have been isolated and characterized [6]. A scheme for the biosynthesis of linkage unit attached to poly(ribitol phosphate) in S. aureus, or poly(N-acetylglucosamine-1-phosphate) in M. varians, involving these 3 lipids (identified as lipids I, II and III, respectively) has been presented [6].…”

“…Alternatively, the third glycerol phosphate residue might not be derived from CDP-glycerol, for example, if it was transferred from lipoteichoic acid carrier (LTC) [6]. The structure of LTC is unclear, but it probably contains glycerol phosphate [14].…”