Inhibition and enhancement of cephalosporin beta-lactamase activity by specific antisera

1970 ◽  
Vol 16 (8) ◽  
pp. 647-650 ◽  
Author(s):  
D. V. Chong ◽  
M. Goldner
Keyword(s):  
Enzyme Activity ◽  
Spectrophotometric Method ◽  
Enzyme Preparation ◽  
Enterobacter Cloacae ◽  
Beta Lactamase ◽  
Cross Reactions ◽  
Bacterial Enzyme ◽  
Specific Antisera ◽  
The Cross ◽  
Different Strains

Certain penicillin beta-lactamase antisera have been reported to enhance, rather than neutralize, the bacterial enzyme activity. A similar study with antisera to cephalosporin beta-lactamase from two different strains of Enterobacter cloacae was undertaken. The effects of the antisera from rabbits immunized with each enzyme preparation were evaluated by neutralization tests using a spectrophotometric method. The antisera were also examined by immunoelectrophoresis. From the neutralization tests, it was observed that either an inhibition or an enhancement of the cephalosporin beta-lactamase activity occurred in the presence of antisera produced in different rabbits under the same conditions and to the same antigen. The inhibiting antisera to the beta-lactamase from each of the two strains were shown to cross-react by neutralization and immunoprecipitin tests; similarly, the two enhancing antisera were also shown to cross-react. Either inhibition or enhancement of the enzyme activity could be obtained with the cross-reactions and with one strain these effects were even greater than with the homologous reactions. The immunoprecipitin results revealed apparent differences between the inhibiting and enhancing antisera.

scholarly journals Serological studies ofBacteroides fragilis

1977 ◽  
Vol 79 (2) ◽  
pp. 233-241 ◽  
Author(s):  
K. M. Elhag ◽  
K. A. Bettelheim ◽  
Soad Tabaqchali
Keyword(s):  
Bacteroides Fragilis ◽  
Gram Negative ◽  
Biochemical Characteristics ◽  
Cross Reactions ◽  
Homologous Antigen ◽  
Specific Antisera ◽  
Serological Studies ◽  
The Cross ◽  
O Antigens

SUMMARYUsing direct agglutination methods, a simple serological scheme for the classification ofBacteroides fragilisis described. Twenty strains ofB. fragiliswere selected by a process of successive screening from 151 strains obtained from various sources. O-antigens were prepared from the 20 strains, and used to raise antisera in rabbits.Each of the 20 antisera reacted with its homologous antigen and eight antisera cross-reacted with other subspecies. These cross-reactions were successfully removed after absorption of the antisera with the cross-reacting antigens, resulting in 19 type-specific antisera, titres ranging from 40 to 320, and 19 distinct serotypes ofB. fragilis. There was no correlation between the antigenic and the biochemical characteristics of these strains and no cross-reactions occurred with other gram-negative anaerobes,B. melaninogenicus, Sphaerophorus necrophorusandFuso-bacterium necrogenes.

scholarly journals STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI

1944 ◽  
Vol 79 (1) ◽  
pp. 99-114 ◽  
Author(s):  
Walter A. Stewart ◽  
Rebecca C. Lancefield ◽  
Armine T. Wilson ◽  
Homer F. Swift
Keyword(s):  
T Antigen ◽  
T Antigens ◽  
Antigenic Composition ◽  
Slide Agglutination ◽  
Cross Reactions ◽  
Specific Antisera ◽  
Group A ◽  
The Cross

1. The occurrence of closely related T antigens in the series composed of types 15, 17, 19, 23, and 30 accounts for most of the cross reactions observed among these types. Similarly T antigens, unrelated to the first series but mutually related, occur in a second series comprising types 4, 24, 26, 28, 29, and 46. 2. Matt variants of each of the eleven types studied possess type-specific M antigens demonstrable either by precipitin or agglutinin reactions. 3. In seven of these types, strains have been encountered which do not possess the T antigen usually associated with the type in question. 4. Procedures are outlined in the appendix for preparing specific antisera for the classification of these types by the slide agglutination technique.

scholarly journals Naturally induced auto-anit-idiotypic antibodies. Induction by identical idiotopes in some members of an outbred rabbit family.

1982 ◽  
Vol 156 (3) ◽  
pp. 860-872 ◽  
Author(s):  
S B Binion ◽  
L S Rodkey
Keyword(s):  
Germ Line ◽  
Antibody Responses ◽  
Idiotypic Network ◽  
Paternal Origin ◽  
Cross Reactions ◽  
Network Concept ◽  
Normal Individuals ◽  
Micrococcus Lysodeikticus ◽  
The Cross ◽  
Antibody Population

Naturally induced auto-anti-idiotypic (AAI) antibody responses specific for antimicrococcal antibody idiotypes were detected in 42% of the rabbits in a family immunized with Micrococcus lysodeikticus. The natural AAI response of each rabbit recognized only a portion (11-41%) of that individual's total antimicrococcal antibody population. Cross-reactions of idiotypes were observed within the group of rabbits exhibiting natural AAI responses. Examination of the basis for the cross-reactions showed that the natural AAI antisera recognized identical idiotopes on the antimicrococcal F(ab')2 fragments from each rabbit that made an AAI response. The cross-reactive idiotopes were shown to be of paternal origin and were found in the antimicrococcal antibodies of each offspring. The data strongly support the idiotypic network concept that naturally induced AAI responses may occur routinely in outbred normal individuals as a result of antigenic stimulation. Further, the data suggest that the induction of regulatory AAI antibody responses in outbred rabbits may depend on the expression of particular germ line idiotopes.

scholarly journals Purification and subunit structure of argininosuccinate lyase from Chlamydomonas reinhardi

1977 ◽  
Vol 167 (1) ◽  
pp. 71-75 ◽  
Author(s):  
R F Matagne ◽  
J P Schlösser
Keyword(s):  
Enzyme Activity ◽  
Crude Extract ◽  
Enzyme Preparation ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Activity Analysis ◽  
Disc Electrophoresis ◽  
Subunit Structure ◽  
Argininosuccinate Lyase

Argininosuccinate lyase (EC 4.3.2.1) was purified by (NH4)2SO4 fractionation, chromatography on DEAE-cellulose and gel filtration on Sephadex G-200. The final enzyme preparation was purified 46-fold compared with the crude extract. Electrophoresis of this preparation revealed three bands, the major one having the enzyme activity. Analysis of the enzyme by gel filtration and by disc electrophoresis (in two different concentrations of acrylamide) gave mol.wts. of 200000 (+/- 15000) and 190000 (+/- 20000) respectively. Treatment with sodium dodecyl sulphate and mercaptoethanol dissociated the enzyme into subunits of mol.wt. 39000 (+/-2000). The results are indicative of the multimeric structure of the enzyme, which is composed of five (perhaps four or six) identical subunits.

scholarly journals Interaction of soluble glucosyl- and mannosyl-transferase enzyme activities in the synthesis of a glucomannan

1972 ◽  
Vol 129 (3) ◽  
pp. 645-655 ◽  
Author(s):  
J. S. Heller ◽  
C. L. Villemez
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Enzyme Preparation ◽  
The Other ◽  
Acceptor Molecule ◽  
Soluble Enzyme ◽  
Phaseolus Aureus ◽  
Polymeric Product ◽  
Sugar Nucleotide ◽  
Solubilized Enzyme

A neutral-detergent-solubilized-enzyme preparation derived from Phaseolus aureus hypocotyls contains two types of glycosyltransferase activity. One, mannosyltransferase enzyme activity, utilizes GDP-α-d-mannose as the sugar nucleotide substrate. The other, glucosyltransferase enzyme activity, utilizes GDP-α-d-glucose as the sugar nucleotide substrate. The soluble enzyme preparation catalyses the formation of what appears to be a homopolysaccharide when either sugar nucleotide is the only substrate present. A β-(1→4)-linked mannan is the only polymeric product when only GDP-α-d-mannose is added. A β-(1→4)-linked glucan is the only polymeric product when only GDP-α-d-glucose is added. In the presence of both sugar nucleotides, however, a β-(1→4)-linked glucomannan is formed. There are indications that endogenous sugar donors may be present in the enzyme preparation. There appear to be only two glycosyltransferases in the enzyme preparation, each catalysing the transfer of a different sugar to the same type of acceptor molecule. The glucosyltransferase requires the continual production of mannose-containing acceptor molecules for maintenance of enzyme activity, and is thereby dependent upon the activity of the mannosyltransferase. The mannosyltransferase, on the other hand, does not require the continual production of glucose-containing acceptors for maintenance of enzyme activity, but is severely inhibited by GDP-α-P-glucose. These properties promote the synthesis of β-(1→4)-linked glucomannan rather than β-(1→4)-linked glucan plus β-(1→4)-linked mannan when both sugar nucleotide substrates are present.

Use of a reversed-phase evaporation vesicle formulation for a homogeneous liposome immunoassay.

1986 ◽  
Vol 32 (9) ◽  
pp. 1687-1691 ◽  
Author(s):  
E Canova-Davis ◽  
C T Redemann ◽  
Y P Vollmer ◽  
V T Kung
Keyword(s):  
Enzyme Activity ◽  
Colorimetric Detection ◽  
Reversed Phase ◽  
Homogeneous Immunoassay ◽  
Bacterial Enzyme ◽  
Liposome Preparation ◽  
Enzyme Molecules ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Relevant Range ◽  
Serum Components

Abstract Complement-mediated release of enzyme molecules from reversed-phase evaporation vesicles serves as the basis of the sensitive homogeneous immunoassay reported here. We found it necessary to co-entrap the substrate glucose 6-phosphate with the bacterial enzyme glucose-6-phosphate dehydrogenase (EC 1.1.1.49) to protect enzyme activity during liposome preparation. Enzyme can be released specifically from these liposomes by incubation with antibody and complement. the enzyme is not merely available to substrate but is actually physically free of the liposomes. Inhibition of this complement-mediated lysis by theophylline is the basis for the homogeneous liposome immunoassay described. The assay results vary linearly with theophylline concentrations in plasma in the clinically relevant range, and serum components do not interfere. The reagents in the assay kit are stable for at least seven months when stored at 5 degrees C. No nontheophylline compounds reacted significantly with the antiserum used. The assay can be run in a kinetic format, with either ultraviolet or colorimetric detection.

Bg^b Expression in Relation to the HLA-B17 Antigen Splits Bw57 and Bw58 and the Cross-Reactions of Anti-Bg^b Antibodies

Vox Sanguinis ◽  
1982 ◽  
Vol 43 (1) ◽  
pp. 1-10
Author(s):  
Marilyn S. Pollack ◽  
Mary N. Crawford ◽  
Harriet M. Robinson ◽  
Rachel Berger ◽  
Bernice Sabo ◽  
...  
Keyword(s):  
Cross Reactions ◽  
The Cross
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