Abstract
1. The genetic determinant of O-antigen 5 in Salmonella group B, which is related to a blood group A-active Forssman antigen FA, is considered to be situated near his lous, though not so near as those of O-antigen 4 or 9, and not far away from met locus.
The locus of genetic determinant of O-antigen 5 is at least outside the range of co-transduction with his+ by phage P22 (iota).
2. The O-antigen 4 is transferred to S. typhi (F- ; O-9, 12) by mating with S. abony (Hfr; O-1, 4, 5, 12).
The determinant of O-antigen 4 or 9 is found closely linked to the his gene, and cotransduction of these determinants is accomplished with phage P22 (iota). These results indicate that the genetic determinants of O-antigens 4 and 9 are probably allelic.
3. The mutual conjugation hybrids among Salmonella groups B (S. abony, O-1, 4, 5, 12 ; S. paratyphi var, odense, O-1, 4, 12), D (S. typhi, O-9, 12), G (S. poona, O-13, 22 ; S. grumpensis, O-13, 23), R (S. riojrande, O-40) and U (S. milwaukee, O-43) which receive O-antigens with O-antigen-related blood group activities of donors concurrently lose O-antigens with O-antigen related blood group activities of recipients.
These results suggest that the loci of genetic determinants which control the production-not only of O-antigen 4, (12), 9, (12) but also of blood group H-active O-antigen 13 (H), 22, 23, A-active O-antigen 40 and B-active O-antigen 43 may be closely linked with his loci respectively, and allelic with each other.
4. S. paratyphi var. odense (native O-antigen 1, 4, 12) of group B, which was transferred O-13, 23 ; O-40 or O-43, has P22 (iota) without manifestation of O-1, but it is manifested after transfer of O-antigen 4, (5), 12 of S. paratyphi B 8006 of group B or of O-antigen 9, 12 of S. typhi of group D by recombination.
This is considered to indicate that O-antigen 1 may be produced through the action of phage P22 (iota) in the course of production of O-antigen 12.
