the mechanism by which Salmonella poly H
serum prevents growth and metabolism of Salmonella
is not clear. Altough both Salmonella
poly 0 and poly H sera agglutinate Salmonella,
there was no effect on metabolism growth, or
both, Salmonella (as measured by the '4CO2
produced from ["C]dulcitol) when Salmonella
poly 0 serum was added to the culture medium.
However, the results were clearly positive when
the radiometric method was tested with poly H
sera and pure cultures of the nonmotile strains
S. pullorum and S. gallinarum. When 106 cells
of S. pullorum or S. gallinarum were used as
the inoculum, the responses were similar to that
of S. newport (Fig. lb). The ratio of radioactivity
from flask A to that from flask B was 4.5:1 after
7 h for both nonmotile strains. The effect on
metabolism may be due to antibody to some
other component of the bacterial cell, e.g., transport
proteins, concomitantly present in the poly
H serum.