Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incubation of human leukocytes with a urea extract of Bordetella pertussis led to inhibition of zymosan-induced leukotriene generation. The proteins in this extract are known to include an adenylate cyclase which suppresses certain defense mechanisms of leukocytes against bacterial invasion. The formation of leukotriene B4 and leukotriene C4, induced by serum-coated zymosan, was almost completely inhibited in the presence of 75 micrograms of urea-extracted proteins/ml cell suspension. This suppression by the bacterial urea extract was rapid, with the maximum effect occurring in the first min of incubation. The reduction in leukotriene generation was accompanied by a dramatic increase in intracellular cyclic AMP levels. Since leukotrienes are potent pro-inflammatory compounds, the present study indicates that Bordetella pertussis-induced suppression of leukotriene formation might be an important factor in the increased susceptibility to secondary bacterial infection, which occurs as a result of this disease.
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PMID:Suppression of leukotriene synthesis in human leukocytes by a urea extract of Bordetella pertussis: evidence for mediation by adenylate cyclase toxin. 285 62

The existence of an invasive adenylate cyclase in dialyzed urea extracts of the bacterium Bordetella pertussis has been suggested recently. Gel filtration of B. pertussis dialyzed urea extract shows that the invasive enzyme constitutes only a small portion of the total adenylate cyclase activity found in the extract. Its size is different than the size of the two peaks of adenylate cyclase activity identified in the extract. Ca2+ is absolutely required for the penetration of the invasive enzyme, it also controls the rate of intracellular cAMP accumulation in human lymphocytes exposed to dialyzed extract. These characteristics may be attributed to the increase in the size of the invasive enzyme as found by gel filtration chromatography of the extract in the absence of Ca2+. Removal of nonpenetrating adenylate cyclase that adheres to lymphocytes permits a direct assay of the intracellular enzyme. The time course of intracellular accumulation of adenylate cyclase activity is similar to the time course of intracellular accumulation of cAMP, suggesting that the invasive enzyme is rapidly deactivated, but not degraded, since it can be detected upon cell disruption. No appreciable amount of the enzyme is introduced when cells are incubated with extract at 4 degrees C for 120 min, then washed and incubated further at 37 degrees C. Concanavalin A inhibits cAMP accumulation irrespective of the time of its addition, and EGTA prevents penetration of the invasive enzyme even if added 20 min after addition of extract. These findings are different from those observed in other bacterial toxins thought to be internalized by receptor-mediated endocytosis. However, the cellular penetration of B. pertussis adenylate cyclase is cell-selective. It does not occur in human erythrocytes. In addition to human lymphocytes, S49 cyc- murine lymphoma, turkey erythrocytes, and rat oocytes accumulate cAMP in response to B. pertussis extract.
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PMID:Bordetella pertussis invasive adenylate cyclase. Partial resolution and properties of its cellular penetration. 285 87

The extracellular adenylate cyclase of Bordetella pertussis was partially purified and found to contain high- and low-molecular-weight species. The high-molecular-weight form had a variable molecular weight with a peak at about 700,000. The smaller species had a molecular weight of 60 to 70,000 as determined by gel filtration. The low-molecular-weight form could be derived from the high-molecular-weight species. The high-molecular-weight complex purified from the cellular supernatant was highly stimulated by calmodulin, while the low-molecular-weight enzyme was much less stimulated. Active enzyme could be recovered from sodium dodecyl sulfate (SDS) gels at positions corresponding to molecular weights of about 50,000 and 65,000. Active low-molecular-weight enzyme recovered from SDS gels migrated with a molecular weight of about 50,000, which coincides with a coomassie blue-stained band. However, when both high- and low-molecular weight preparations were analyzed in 8 M urea isoelectrofocusing gels, the enzyme activity recovered did not comigrate with stained protein bands. The enzyme recovered from denaturing isoelectrofocusing or SDS gels was activated by calmodulin, indicating a direct interaction of calmodulin and enzyme. The high-molecular-weight form of the enzyme showed increasing activity with calmodulin concentrations ranging from 0.1 to 500 nM, while the low-molecular-weight form was fully activated by calmodulin at 20 nM. Adenylate cyclase on the surface of living cells was activated by calmodulin in a manner which resembled that found for the high-molecular-weight form.
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PMID:Secreted adenylate cyclase of Bordetella pertussis: calmodulin requirements and partial purification of two forms. 287 55

Purified preparations of adenylate cyclase were obtained from crude urea extracts of Bordetella pertussis by a one-step calmodulin affinity chromatography technique. Diluted extract was loaded onto the column and washed, and adenylate cyclase was eluted with 10mM EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid]. A 104-fold purification was accomplished in one step. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the affinity-purified adenylate cyclase was dissociated into one major protein band with an apparent molecular weight of 60,000 and a minor band at 200,000. The affinity-purified adenylate cyclase was observed to have adenylate cyclase enzymatic activity which was activated by calmodulin, to bind 125I-calmodulin, and to be free of pertussis toxin as determined by in vivo and in vitro assays.
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PMID:Bordetella pertussis adenylate cyclase: isolation and purification by calmodulin-sepharose 4B chromatography. 287 83

Fimbriae were removed from Bordetella pertussis (serotype 1.3.6) by mechanical shearing and purified by precipitation with ammonium sulfate, pH-dependent precipitation at pH 7.4, followed by two successive extractions of the precipitated fimbriae with 4 M urea. By electron microscopy, the precipitated fimbriae appeared as aggregated bundles of long, relatively straight filaments which were disaggregated to individual flexuous filaments at pH 10.5. These purified fimbriae were identified as serotype 6 agglutinogens, since antibody to the purified fimbriae agglutinated B. pertussis strains serotyped as 1.3.6, 1.2.3.6, or 1.2.3.4.6 but did not agglutinate strains of serotype 1.2.3.4, 1.2.3, or 1.3. In contrast, antibody to serotype 2 fimbriae only agglutinated B. pertussis strains containing serotype 2 agglutinogen. Purified type 6 and 2 fimbriae were found to be weakly cross-reactive by enzyme-linked immunosorbent assay, using polyclonal antibody to each type of fimbria. In an immunoblot assay, polyclonal antibodies to a 22,000-dalton subunit of fimbriae from B. bronchiseptica reacted strongly with the type 2 fimbrial subunit of B. pertussis, but only weakly with the type 6 subunit. When subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the protein subunit of the type 6 fimbriae migrated with a molecular weight of 21,500, whereas the type 2 fimbrial subunit had a molecular weight of 22,000. The two types of subunits had similar amino acid compositions and showed amino-terminal sequence homology in 15 of 21 amino acids. The amino-terminal amino acid sequences of the B. pertussis fimbriae were distinct from those reported for fimbriae from other gram-negative bacteria. Neither the type 6 nor the type 2 fimbriae caused hemagglutination when assayed with several types of erythrocytes.
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PMID:Purification and characterization of serotype 6 fimbriae from Bordetella pertussis and comparison of their properties with serotype 2 fimbriae. 288 93

Exposure of Chinese hamster ovary, mouse adrenal cortex tumor (Y-1), THP-1 and U-937 cells and human erythrocytes to adenylate-cyclase-containing urea extracts of Bordetella pertussis (strain 114) organisms promotes the formation of large concentrations of intracellular cAMP. Accumulation is dependent on dose and temperature, with significant accumulation occurring at 4 degrees C, and is virtually instantaneous, with a doubling at 1 min. There is an absolute Ca2+ requirement but external calmodulin (the activator of cyclase activity) has no effect except in erythrocytes and U-937 cells, where it reduces cAMP accumulation. However, calmodulin antagonists inhibit cAMP accumulation. In Y-1 adrenal cells the urea-extract adenylate cyclase stimulates steroidogenesis. Anti-(B. pertussis) antibodies inhibit cyclase activity and prevent further cAMP accumulation after 10 min in cells previously exposed to urea extract. The same effect is obtained by washing. This suggests that a portion of the cyclase is associated with cells in a form not accessible to antibody or washing but accessible to substrate, which we interpret as internalized enzyme with a short lifetime. Continuing cAMP accumulation thus appears to need a continuing source of external cyclase. Inhibitors of the effect of diphtheria toxin, such as NH4Cl, methylamine, chloroquine or monensin, have no inhibitory effect on the accumulation of intracellular cAMP promoted by the internalized adenylate cyclase of urea extracts of B. pertussis organisms. We conclude that entry of the cyclase into cells is not by receptor-mediated endocytosis.
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PMID:Bordetella pertussis adenylate cyclase. Penetration into host cells. 290 Jul 63

Two forms of Bordetella pertussis adenylate cyclase of 200 and 47 kDa have been purified from dialyzed urea extract of the bacteria to specific activities of 466 and 1685 mumol.min-1.mg-1, respectively. Both forms are activated 50-200-fold by calmodulin. The half-maximum concentration required for the activation of the 200-kDa catalyst is 5.4.10(-9) M, whereas the one required for activation of the 47-kDa catalyst is 1.8.10(-10) M. Polyclonal antibodies raised against the 47-kDa catalyst specifically recognize both forms of the enzyme in purified state as well as in bacterial extracts on immunoblots. The antibody inhibits at similar titer adenylate cyclase activity of the purified forms as well as the activity present in dialyzed urea extract of the bacteria. It also prevents the penetration of the invasive B. pertussis adenylate cyclase into human lymphocytes. The inhibition induced by the antisera is specific to B. pertussis enzyme, since both calmodulin-dependent brain and sperm adenylate cyclase are not affected by the antibody.
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PMID:Bordetella pertussis adenylate cyclase. Identification of multiple forms of the enzyme by antibodies. 290 13

A recombinant plasmid, pRMB1, identified from a gene library of B. pertussis, restored adenylate cyclase (AC) and haemolysin (HLY) activities to B. pertussis BP348 (a Tn5-insertion mutant deficient in both these activities). B. pertussis BP348 was considerably less virulent than wild type strains of B. pertussis when 3-week-old mice were challenged intranasally; possession of pRMB1 restored virulence. Neither AC nor HLY activities were expressed in E. coli harbouring pRMB1. However, expression of calmodulin-responsive AC was obtained in E. coli when restriction fragments of pRMB1 were subcloned into other vectors; expression depended on the lac and tac promoters of these vectors. The enzyme was not readily solubilized from urea extracts of E. coli and required sonication for efficient release. One plasmid conferred a specific AC enzymic activity to E. coli which was greater than that for wild type B. pertussis strains. Unlike extracts of B. pertussis, extracts from E. coli expressing enzymic AC activity, did not elevate cAMP levels in S49 lymphoma cells. A second plasmid, pRMB2, was identified from the gene library, which contained a trans-acting regulatory determinant required for expression of AC, HLY and other virulence-associated factors in B. pertussis.
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PMID:Cloning of the adenylate cyclase genetic determinant of Bordetella pertussis and its expression in Escherichia coli and B. pertussis. 290 65

Herein we describe the distribution of G-proteins in canine cardiac sarcolemma (SL) and sarcoplasmic reticulum (SR) and in rabbit skeletal muscle SL, T-tubules, and junctional and longitudinal SR in comparison to G-proteins of human erythrocyte and bovine brain. G-proteins were unequivocally present in cardiac SL and SR and in skeletal T-tubules. Both cardiac fractions had two substrates specifically ADP-ribosylated by cholera toxin migrating on a sodium dodecyl sulfate-polyacrylamide gel at about 42 and 45 kDa. In skeletal muscle membranes, cholera toxi-labeled substrates migrated at about 42 and 62 kDa. Three substrates for pertussis toxin were resolved by sodium dodecyl sulfate/urea-polyacrylamide gel electrophoresis in cardiac SL at about 38, 40, and 43 kDa. Only the two higher molecular weight substrates were detected in cardiac SR and in any of several skeletal muscle membrane fractions. Comparison of G-proteins in muscle membrane fractions with G-proteins isolated from bovine brain and human erythrocyte as well as their reaction with antisera to either a common sequence of alpha subunits of G-proteins (G alpha common antibody) or to a unique sequence of the alpha subunit of Go (G alpha o antibody) indicated that the two lower molecular weight bands in cardiac SL are Go or Go-like, and therefore the upper band is probably Gi. These data demonstrate that pertussis toxin substrates are more heterogeneous than previously described and have implications for studies attempting to attribute physiological functions to G-protein isolates.
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PMID:G-protein distribution in canine cardiac sarcoplasmic reticulum and sarcolemma: comparison to rabbit skeletal muscle membranes and to brain and erythrocyte G-proteins. 312 62

The purified toxin of Bordetella pertussis was dissociated in 5 M urea in the presence of immobilized haptoglobin. The toxin was dissociated in free S1, free S5 and the free complexes S2-S4 and S3-S4, with S2-S4 as the only haptoglobin-binding moiety, identifying S2 as the haptoglobin-binding protein. Partial NH2-terminal amino acid sequences were obtained from the dissimilar toxin subunits, after separation by SDS-polyacrylamide gel electrophoresis followed by electroblotting onto polybrene-coated glass-fiber sheets. The sequences reveal extensive homology of the N-terminal portions of the constitutive subunits S2 and S3 and between S1 and the enterotoxin A chains of Vibrio cholerae and Escherichia coli.
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PMID:Protein-chemical analysis of pertussis toxin reveals homology between the subunits S2 and S3, between S1 and the A chains of enterotoxins of Vibrio cholerae and Escherichia coli and identifies S2 as the haptoglobin-binding subunit. 352 28


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