: four a.a. are sequentially added to NAM
forming a tetrapeptide
(2) Cell Membrane
: NAM- tetrapeptide is attached to the bactoprenol (
- The NAG
is attached to the NAM-tetrapeptide on the bactoprenol to complete the peptidoglycan monomer.
(3) ) Peptidoglycan monomers are transported
into periplasmic space
(4) Periplasm: autolysins break
the glycosidic bonds
btwn the peptidoglycan monomers at the point of growth along the existing peptidoglycan.
- They also break the peptide cross-bridges (pentaglycine peptides) that link the rows of
- sugars together
In this way, new peptidoglycan monomers can be inserted.
(5) Transglycosylase (TG)
enzymes catalyze the formation of glycosidic bonds btwn NAM and NAG
of the peptidoglycan momomers and the NAG and NAM of the existing peptidoglycan.
(6) transpeptidase (TP)
enzymes reform the peptide cross-links (pentaglycine peptides) btwn the rows and layers of peptidoglycan to make the wall strong