Sbarra, Anthony J. (St. Margaret's Hospital, Boston, Mass.), William Shirley, and John S. Baumstark. Effect of osmolarity on phagocytosis. J. Bacteriol. 85:306-313. 1963.-The effect of a number of different compounds on phagocytosis was studied. Phagocytosis was monitored by morphological and biochemical means. It was found that the addition of compounds such as KCl, NaCl, sodium or potassium malonate, and K(2)SO(4) to the phagocytic system inhibited phagocytosis. The increased salt concentration specifically inhibited the respiratory activity associated with phagocytosis. The endogenous respiration of the leukocytes was unaffected. Glycolysis and the increased flow of glucose through the hexose monophosphate pathway were also inhibited by the elevated concentration of salts. In addition, cells exposed to high salt concentrations appeared to be reduced in size as compared with normal cells. The inhibition can be reversed by lowering the salt concentration. It was suggested that the increased osmotic pressure of the system was responsible for the inhibition.

Glucose↗

PubMed1963

Serology of Listeria monocytogenes. I. Characteristics of the soluble hemolysin.

Girard, Kenneth F. (St. Margaret's Hospital, Boston, Mass.), Anthony J. Sbarra, and Wadi A. Bardawil. Serology of Listeria monocytogenes. I. Characteristics of the soluble hemolysin. J. Bacteriol. 85:349-355. 1963.-Our results clearly demonstrate that Listeria monocytogenes (strain 9-125) produces a soluble hemolysin. Such hemolysin is completely precipitated out of sterile culture filtrates by 60% saturation with ammonium sulfate at 5 C, and virtually all of the hemolytic activity resides in the so-called "euglobulin" fraction. The protein nature of this hemolysin is further indicated by its nondialyzable property, heat lability, susceptibility to proteolysis by trypsin, and antigenicity in the full sense. Paper electrophoresis indicates that the isolated active fraction migrates as a gamma-type globulin. A procedure for determining Listeria antihemolysin levels in sera adapted from a method commonly employed for quantitating antistreptolysin O is described. The relative value of anti-Listeria hemolysin titration as a possible serological aid in diagnosis remains to be determined and is presently under investigation.

Hemolysin Proteins↗

PubMed1963

PHAGOCYTOSIS INHIBITION AND REVERSAL. I. EFFECT OF GLYCOLYTIC INTERMEDIATES AND NUCLEOTIDES ON PARTICLE UPTAKE.

Sbarra, Anthony J. (St. Margaret's Hospital, Boston, Mass.) and William Shirley. Phagocytosis inhibition and reversal. I. Effect of glycolytic intermediates and nucleotides on particle uptake. J. Bacteriol. 86:259-265. 1963.-By microscopically monitoring phagocytosis and following the biochemical changes associated with this process, the inhibition of phagocytosis by fluoride or iodoacetate was shown to be partially reversed by pyruvate. This reversal occurred with both inhibitors, either aerobically or anaerobically. Nicotinamide adenine dinucleotide (NAD) apparently increased the degree of pyruvate reversal when fluoride, but not iodoacetate, was the inhibitory agent. Lactate under some conditions was also shown to reverse the inhibition. It is suggested that pyruvate and NAD are key compounds for the phagocytic process.

Fluorides↗

PubMed1962