ABSTRACT
Addition of ppApp to Sterlini-Mandelstam medium stimulates sporulation of a conditionally asporogenous rifampin-resistant mutant of Bacillus subtilis to the same extent as the effect of 4 amino acids. Mutant cells sporulating in the presence of amino acids also produce 2 phosphorylated nucleotides one of which comigrated with ppApp on PEI thin layer chromatogram.
Subject(s)
Adenine Nucleotides/pharmacology , Bacillus subtilis/physiology , Rifampin/pharmacology , Adenine/pharmacology , Adenosine Monophosphate/pharmacology , Amino Acids/pharmacology , Bacillus subtilis/drug effects , Drug Resistance, Microbial , Kinetics , Spores, Bacterial/drug effects , Spores, Bacterial/physiologyABSTRACT
The purpose of this study was to characterize the effects of allogenic splenocytes transferred with tumor cells, subcutaneously, to a host syngenic for tumor cells. Cytotoxic effector cells usually resulted in tumors less than half the size of controls at E:T of 10:1. Primary immune splenocytes were more effective than hyperimmune splenocytes in delaying tumor growth. Actively cytotoxic splenocytes by in vitro 51Cr release assay were required for delayed tumor growth; memory cell populations were not effective. Delayed tumor growth correlated with in vitro cytotoxicity of primary immune splenocytes; however, hyperimmune splenocytes, even though they possessed greater in vitro cytotoxic responses, showed lesser tumor suppression in vivo. T cells were necessary for tumor suppression, as treatment of B6AF1 effector cells with anti-Thy 1.2 serum abrogated suppression; T cell enrichment by nylon-wool treatment of effector cells increased tumor suppression. Delay in tumor growth was an in vivo phenomenon, for anti-Thy 1.2 serum in AKR hosts abrogated the effect of Thy 1.2 effector cells.
Subject(s)
H-2 Antigens , Neoplasms, Experimental/immunology , T-Lymphocytes/immunology , Animals , Antilymphocyte Serum/pharmacology , Cytotoxicity, Immunologic , Immunotherapy , Mice , Mice, Inbred AKR , Mice, Inbred DBA , Models, Biological , Neoplasm Transplantation , Neoplasms, Experimental/therapy , Transplantation, HomologousABSTRACT
A rifampin-resistant, conditionally asporgoenous mutant of Bacillus subtilis was isolated that sporulates poorly in Sterlini-Mandelstam sporulation medium, but that sporulates normally in modified Difco sporulation medium. Rifampin-resistant (Rif-r) and conditional asporogenous (Spo-c) phenotypes co-transformed at 100% frequency. Preliminary genetic studies indicated the Rif-r trait to lie between cysA14 and ery, a locus (rnp) common to Rif-r mutants. Ribonucleic acid polymerase from strains bearing this mutation was found to be rifampin resistant in vitro. The loss of ability to sporulate in Sterlini-Mandelstam medium was found to be corrected, to a large extent, by addition to the medium of arginine, methionine, valine, and isoleucine. Several other amino acids had small effects, whereas others had no effect at all. The restorative effect is approximately additive. Growth studies indicated that Rif-r strains grew more rapidly than the corresponding parent in minimal medium at temperatures higher than 37 C. Addition of certain amino acids to the medium resulted in identical growth rates at these temperatures. Extracellular protease and esterase activities of the Rif-r Spo-c mutant were normal. A slight difference was found in the heat sensitivity of partially purified ribonucleic acid polymerase preparations of this mutant compared to the wild type.