Genetics and Genomics Commons^™

Activation Of B Lymphocytes By Monovalent Anti-Lyb-2 Antibodies, Subbarao Bondada, D. E. Mosier

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Small resting B lymphocytes are activated when their cell surface immuno-globulin (Ig) receptors interact with specific antigen or anti-Ig antibodies. Such a receptor-ligand interaction leads to enlargement and proliferation of B lymphocytes. These activated B cells can subsequently mature into Ig-secreting cells in the presence of appropriate accessory cell signals (1-3). However, monovalent anti-Ig antibodies cannot induce B cell activation even though they can bind to the surface Ig (4-7). It has thus been concluded that membrane Ig has to be cross-linked to induce early steps in B cell activation (membrane depolarization; 8) as well as later steps (proliferation). T …

Interpopulation Variation In Calcareous And Proteinaceous Shell Components In The Stream Limpet, Ferrissia Rivularis, Carl M. Way, Daniel J. Hornbach, Albert J. Burky

Biology Faculty Publications

Natural populations of the North American stream limpet, F. rivularis, were studied in upstate New York [USA], in a set of localities whose waters have a 15-fold range of dissolved Ca (4.6-67.6 mg/liter) and also range from oligotrophy to eutrophy. Shell component analyses (CaCO3, total organic C and total N) are reported as component mass-fractions (mg/g or .mu.g/g dry weight) and as values for a standard limpet shell of 35 mm aperture length (AL). More than 2-fold differences occur between populations in all 3 components, with relatively little variation occurring within each population. Expressed per standard limpet, CaCO3 values for …

Seasonal Metabolism Of The Sphaeriid Clam, Musculium Partumeium (Say), From A Permanent And A Temporary Pond, Carl M. Way, Daniel J. Hornbach, Albert J. Burky

Biology Faculty Publications

Seasonal metabolic rates were examined for the sphaeriid clam, Musculium partumeium (Say) from a permanent and a temporary pond. For the fall-born generation from the permanent pond and for the single generation from the temporary pond, metabolic rates peak during periods of greatest growth and reproduction. Metabolic rates were consistently higher for the permanent pond population. These rates for Musculium partumeium extend the available information on the family Sphaeriidae to the genus Musculium.

Growth Of Pisidium Casertanum (Poli) In West Central Ohio, Albert J. Burky, Daniel J. Hornbach, Carl M. Way

Biology Faculty Publications

Clarke (1973) states that Pisidium casertanum (Poli) is perhaps the most common species of Pisidium and is truly cosmopolitan, occurring throughout Eurasia, Africa, Australia, and South, Central and North America. Populations of these clams are reported in habitats ranging from ephemeral ponds to benthic zones of deep lakes. Our study describes Manuscript received 29 May 1979 and in revised form 25 July 1980 (#79-34). 2 Present address: Department of Biology, University of Virginia, Charlottesville, VA 22901. 3 Present address: Department of Zoology, Miami University, Oxford, OH 45056. 41 aspects of the life-cycle of P. casertanum in a spring-fed stream with …

Role Of A Nonimmunoglobulin Cell Surface Determinant In The Activation Of B Lymphocytes By Thymus-Independent Antigens*, Subbarao Bondada, Donald E. Mosier, Aftab Ahmed, James J. Mond, Irwin Scher, William E. Paul

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Lyb 5 is a B-cell alloantigen which is expressed on 50-60% of B cells. It was defined originally on the basis of cytotoxicity. We have described a new reactivity within the anti-Lyb 5 serum on the basis of selective inhibition of antibody responses in vitro by this antiserum in the absence of complement. This inhibitory activity of anti-Lyb 5.1 serum appears to be due to recognition of antigenic determinants different from the prototype antigens detected in the cytotoxicity assay. Anti-Lyb 5 serum incorporated into spleen cell cultures selectively inhibits antibody responses to a class of thymus-independent antigens (TI-2) previously characterized …

Tritium (3h) Radiolabeling Of Protein A And Antibody To High Specific Activity: Application To Cell Surface Antigen Radioimmunoassays, Ronald L. Wilder, Catherine C. Yuen, Subbarao Bondada, Virgil L. Woods, Cornelius B. Alexander, Rose G. Mage

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Staphylococcal protein A and several different immunoglobulins have been radio-labeled to high specific activities (> 106 cpm/pg) by reductive methylation with tritiated (3H) sodium borohydride. The proteins retain excellent functional and antigenic properties. The utility of these reagents in a variety of assays for cell surface antigens is illustrated. The results indicate that this radiolabeling procedure may become the method of choice for many cell surface and solution immunoassays.

Buoyancy Changes As Related To Respiratory Behavior In An Amphibious Snail, Pomacea Urceus (Müller), From Venezuela, Kathleen A. Burky, Albert J. Burky

Biology Faculty Publications

The ampullariid Pomacea urceus uses its ctenidium and lung in respiration. The snails reach the surface with their siphon and ventilate their lung by withdrawing their head-foot in a pumping action. The lung gas also serves to change the buoyancy of the snails. After a ventilation a snail does not necessarily return to the same buoyancy level. They may achieve overall specific gravities of <1 to > 1 after a ventilation. They may remain submerged (s.g. > 1) or float (s.g.

Inactivation Of Brain Hexokinase By An Adenosine 5'-Triphosphate Analog, Subbarao Bondada, Umakant W. Kenkare

Microbiology, Immunology, and Molecular Genetics Faculty Publications

An analog of ATP, 6-mercapto-9+nribofuranosylpurine 5’-triphosphate (SH-TP), functions as a phosphoryl donor for the reaction catalyzed by hexokinase. Incubation of the enzyme with millimolar concentrations of this reagent led to its rapid inactivation. However, the corresponding monophosphate derivative of this reagent was much less effective. A plot of the initial rate of inactivation versus the concentration of SH-TP exhibited saturation, suggesting the formation of a reversible complex between the enzyme and SH-TP prior to the inactivation reaction. The dissociation constant of this enzyme-inhibitor complex was the same as the K, of this reagent with respect to hexokinase in the phosphoryl …

Reaction Of Brain Hexokinase With Tetranitromethane: Oxidation Of Essential Thiol Groups, Subbarao Bondada, Umakant W. Kenkare

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Treatment of bovine brain mitochondrial hexokinase with a fivefold molar excess of tetranitromethane (TNM) at pH 8.0 results in a complete loss of activity of the enzyme. Spectral measurements and amino acid analysis showed that only cysteinyl residues were modified by TNM under these conditions. The products of the reaction of TNM with the enzyme were cysteic acid and disulfides as found by amino acid analysis of the carboxymethylated hexokinase. Failure of 2-mercaptoethanol to reverse the effect of TNM suggested that the thiol group that is oxidized to cysteic acid is the one essential for enzyme activity. Substrates glucose and …

Molecular Weight Determinations Of Some Salmonella Potsdam Bacteriophage Dna's, Winston H. Richards

Loma Linda University Electronic Theses, Dissertations & Projects

Two group A phages, P9c/2 and P4/2, were studied. Their density, sedimentation velocity, and biochemical properties were compared. Their densities were determined by density gradient centrifugation in 38.3% cesium chloride. Sedimentation velocity was used to determine their molecular weights. To accomplish this, the DNA of P9c/2 and P4/2 was labeled with tritium and T₂ DNA, labeled with ³²P, was used as a standard. The DNA of P9c/2 and P4/2 was separately mixed with T₂ DNA and centrifuged in a 0-15% sucrose gradient. The molecular weights were calculated using the formula D₂/D₁= (M_{2 …}

Biochemical Properties Of Salmonella Potsdam Bacteriophage P4/2, Clyde L. Roggenkamp

Loma Linda University Electronic Theses, Dissertations & Projects

Over 90% recovery of phage P4/2 was realized with differential centrifugation concentration and purification, whereas only about 16% was recovered from the aqueous two-phase polymer - Genetron - ECTEOLA-cellulose column system. Purity of preparations was greatest with the density gradient centrifugation (A₂₆₀ = 2.66 and A₂₈₀ = 1.80 per 10¹² plaque-forming units). With the chemical system of concentration and purification followed by an ECTEOLA anion exchange run, the A₂₆₀ was 6.6 and the A₂₈₀ was 4.3.

Three tests were employed to determine the configuration of P4/2 DNA: (1) a formalin denaturation test, (2) a thermal …

An Experimental Attempt To Modify The Sex Ratio Of Drosophila Melanogaster, Herman Weingrod

Bachelors’ Theses

Sex control has been defined as the science of producing male or female offspring at will by artificial means. Because of the far reaching consequences of such a technique, man has always had a strong desire to control the sex of his offspring. The ancient Egyptians attempted it by means of magic, while the old Hebrew Talmud offered suggestions for its practice based on practical experience. The problem as such forms part of the folklore and superstition of many ancient races and peoples.