ABSTRACT
A diverse range of heterotrophic bacteria was screened for the presence of carbonic anhydrase (CA) activity, sensitivity to inhibition of growth by acetazolamide (CA inhibitor), and the presence of protein binding monospecific antibody prepared against purified Neisseria sicca CA. CA activity was demonstrated only in strains of N. sicca and N. gonorrhoeae. However, all Neisseria strains, including various isolates of N. meningitidis and N. lactamica, were sensitive to acetazolamide, when grown in air, and showed serological cross-reaction with N. sicca CA. Strains of other genera were resistant to acetazolamide. A number of strains including members of the genera Pseudomonas, Staphylococcus, Streptococcus, Serratia and Proteus also strongly expressed a gene product(s) immunologically related to CA. The presence of CA cross-reacting proteins, which lack hydrase activity, is discussed in relation to the function of the various mammalian CA isoenzymes.
Subject(s)
Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Neisseria/enzymology , Acetazolamide/pharmacology , Animals , Clostridium/enzymology , Neisseria/drug effects , Neisseria/growth & development , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/enzymology , Neisseria gonorrhoeae/growth & development , Neisseria meningitidis/drug effects , Neisseria meningitidis/enzymology , Neisseria meningitidis/growth & development , Species SpecificityABSTRACT
Cultures of Neisseria sicca incubated at 37 degrees C died rapidly (within 36 h) after growth ceased. Re-suspending cells in a brain heart infusion broth and storing at 4 degrees C greatly reduced the rate of decline in viability (decimal reduction time 6 days). An important factor in maintaining viability was apparently the presence of external energy source(s). Survival comparable to that in broth was obtained by incubation in Ringer's solution with pyruvate plus glucose (but not with pyruvate or glucose alone). Medium pH had little effect on survival in the range pH 7.0 to 8.5. Energy sources also promoted survival of cells in Ringer's solution or a buffered salts solution at 37 degrees C. Highest levels of survival (up to 30% at 24 h) were obtained with pyruvate, lactate, proline and glutamate. A number of other amino acids and the tricarboxylic acid cycle intermediates, isocitrate, oxoglutarate, succinate, fumarate, malate and oxaloacetate, enhanced survival to a lesser extent.
Subject(s)
Neisseria/growth & development , Brain , Culture Media , Neisseria/cytology , TemperatureABSTRACT
The metabolism of various substrates by non-growing suspensions of Neisseria sicca was investigated by a flow-microcalorimetric technique. Substrate utilisation showed Michaelis kinetics allowing determination of saturation constants (Km) and maximum specific rates of substrate utilisation (Vmax). Pyruvate, lactate, a number of tricarboxylic acid cycle intermediates, and amino acids (aspartate, glutamate and proline) were rapidly metabolised [Vmax 5-35 mumol (g dry wt cells)-1 min-1]; Km values were between 4 and 20 microM. Glucose, glycerol, acetate and the other amino acids investigated gave only a slight or no increase in power. The pattern of substrate utilisation is discussed in relation to the role of carbonic anhydrase in N. sicca.
Subject(s)
Neisseria/metabolism , Acetates/metabolism , Amino Acids/metabolism , Calorimetry , Citric Acid Cycle , Culture Media , Glucose/metabolism , Glycerol/metabolism , Kinetics , Lactates/metabolism , Pyruvates/metabolismABSTRACT
480 pig serum samples collected from November 1979-October 1980 and 200 human sera collected in the same period, nearly have been used in serological investigations. 52.5% sera were positive against swine influenza (HSW1N1) 10% only of human sera were positive against (HSW1N1) virus. By using (H3N2) human virus, 10.4% of pig sera were positive, while 41% of human sera were positive against this virus.
