Reproduced from SciFinder with permission from the Chemical Abstracts Service. The addn. of Na lauryl sulfate [151-21-3] or petroleum ether to Y. pseudotuberculosis grown in a medium contg. 10% glycerol at 28° (conditions under which V and W antigens are not synthesized) significantly increased the phagocytosis of the bacterial cells by rabbit blood. The addn. of Na periodate or trypsin [9002-07-7] produced variable degrees of phagocytosis dependent on the virulence of the strains tested. The role of lipid synthesis in the restoration of phagocytosis at 28° is discussed.