The immunochemistry of peptidoglycan. serological detection of a difference in a single N-terminal amino acid

Antisera to the N-terminal part of pentaglycine or of l-alanyltetraglycine peptides were raised by immunizing rabbits with the peptidyl-proteins (Gly₅-ε{lunate}-Ahx)₂₀-albumin^* or (l-Ala-Gly₄)₁₁-R Nase, respectively. Antisera to (Gly₅-ε{lunate}-Ahx)₂₀-albumin showed a clearcut specificity for pentaglycine but not for l-alanyl-tetraglycine. Antisera to (l-Ala-Gly₄)₁₁-R Nase bound specifically to l-alanyl-tetraglycine but not to pentaglycine. The definite specificity of these antisera permits the serological differentiation of some bacterial strains on the basis of the primary structure of their cell wall peptidoglycans.