Genetic mapping of the K1 and K4 antigens (L) of Escherichia coli. Non-allelism of K(L) antigens with K antigens of O8:K27(A), O8:K8(L) and O9:K57(B).

Escherichia donor strains having antigen K1(L) or K4(L) transfer these K antigens to recipient cells at a genetic locus (kps A) similar to that of K10(L) and K54(L) linked to ser A. In crosses between the K10 donor strain and recipient strains O8:K8(L), O8:K27(A) and O9:K57(B) all recombinants which inherit donor K antigen also inherit K antigen of recipient. This result is interpreted as non-allelism between donor and recipient K antigens, and it is assumed that the structure of all polysaccharide K antigens of strains having O antigens O8 or O9, whether termed L, A, or B, are controlled by genes which differ in their location on the chromosome from genes controlling polysaccharide K antigens associated with most other O antigens.