INHIBITORS OF CARBONIC ANHYDRASE IN THE AMERICAN COCKROACH, PERIPLANETA AMERICANA (L.)

Carbonic anhydrase activity has been demonstrated in vitro in preparations of the head, fat body, and gut of the American cockroach, Periplaneta americana (L.), and in the adult housefly, Musca domestica L. The insect factor, which is soluble in aqueous media and can be separated from the particulate cell fragments of insect tissue homogenates is heat labile and sensitive to cyanide inactivation. It is strongly inhibited by sulphanilamide, p-aminoethylphenyl-sulphonamide, and p-chlorphenylsulphonamide. No inhibition has been found with N-substituted sulphonamides or with any of the organic insecticides examined, including DDT, lindane, dieldrin, nicotine, rotenone, pyrethrins, and para-oxon. Sensitivity of carbonic anhydrase to sulphonamides having an intact—SO2NH2 group is also characteristic of mammalian preparations. The data indicate that inhibition of insect carbonic anhydrase cannot be an important factor in the mode of action of DDT or other organic insecticides.

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On the release and action of the hypertrehalosaemic hormone from the cockroach nauphoeta cinerea

Zeitschrift für Naturforschung C ◽

10.1515/znc-1988-1-221 ◽

1988 ◽

Vol 43 (1-2) ◽

pp. 108-116 ◽

Cited By ~ 10

Author(s):

Gerd Gäde

Keyword(s):

Glycogen Phosphorylase ◽

Periplaneta Americana ◽

Fat Body ◽

Neurosecretory Cells ◽

American Cockroach ◽

Corpora Cardiaca ◽

Nauphoeta Cinerea ◽

Dose Dependent Fashion ◽

Dose Dependent

The corpora cardiaca of the cockroach Nauphoeta cinerea contain a hypertrehalosaemic hormone (HTH) which is chemically characterized as a blocked decapeptide. The synthetic HTH shows the same chromatographic behaviour as the material isolated from corpora cardiaca. The synthetic peptide causes hypertrehalosaemia and fat body glycogen phosphorylase-activation in N. cinerea as well as in the American cockroach, Periplaneta americana in a dose-dependent fashion. It is calculated that one gland from N. cinerea stores about 50 pmol of HTH. Roughly 10% of the total available hormone in the gland is released in vitro during exposure to an elevated potassium saline which causes depolarization of the neurosecretory cells

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The Effect of Cholera Toxin on Choroid Plexus Carbonic Anhydrase Activity In Vitro

Neurological Research ◽

10.1080/01616412.1980.11739564 ◽

1980 ◽

Vol 1 (4) ◽

pp. 333-339

Author(s):

Arthur M. Feldman ◽

Mel H. Epstein ◽

Fallon Maylack ◽

Saul W. Brusilow

Keyword(s):

Carbonic Anhydrase ◽

Choroid Plexus ◽

Cholera Toxin ◽

Carbonic Anhydrase Activity

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The Periplasmic α-Carbonic Anhydrase Activity of Helicobacter pylori Is Essential for Acid Acclimation

Journal of Bacteriology ◽

10.1128/jb.187.2.729-738.2005 ◽

2005 ◽

Vol 187 (2) ◽

pp. 729-738 ◽

Cited By ~ 124

Author(s):

Elizabeth A. Marcus ◽

Amiel P. Moshfegh ◽

George Sachs ◽

David R. Scott

Keyword(s):

Helicobacter Pylori ◽

Membrane Potential ◽

Carbonic Anhydrase ◽

Membrane Integrity ◽

Carbonic Anhydrase Activity ◽

Knockout Mutant ◽

Inner Membrane ◽

Acid Acclimation

ABSTRACT The role of the periplasmic α-carbonic anhydrase (α-CA) (HP1186) in acid acclimation of Helicobacter pylori was investigated. Urease and urea influx through UreI have been shown to be essential for gastric colonization and for acid survival in vitro. Intrabacterial urease generation of NH3 has a major role in regulation of periplasmic pH and inner membrane potential under acidic conditions, allowing adequate bioenergetics for survival and growth. Since α-CA catalyzes the conversion of CO2 to HCO3 −, the role of CO2 in periplasmic buffering was studied using an α-CA deletion mutant and the CA inhibitor acetazolamide. Western analysis confirmed that α-CA was bound to the inner membrane. Immunoblots and PCR confirmed the absence of the enzyme and the gene in the α-CA knockout. In the mutant or in the presence of acetazolamide, there was an ∼3 log10 decrease in acid survival. In acid, absence of α-CA activity decreased membrane integrity, as observed using membrane-permeant and -impermeant fluorescent DNA dyes. The increase in membrane potential and cytoplasmic buffering following urea addition to wild-type organisms in acid was absent in the α-CA knockout mutant and in the presence of acetazolamide, although UreI and urease remained fully functional. At low pH, the elevation of cytoplasmic and periplasmic pH with urea was abolished in the absence of α-CA activity. Hence, buffering of the periplasm to a pH consistent with viability depends not only on NH3 efflux from the cytoplasm but also on the conversion of CO2, produced by urease, to HCO3 − by the periplasmic α-CA.

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Trehalose production in isolated fat body of the american cockroach, Periplaneta americana

Comparative Biochemistry and Physiology Part C Comparative Pharmacology ◽

10.1016/0306-4492(79)90096-0 ◽

1979 ◽

Vol 62 (1) ◽

pp. 31-34 ◽

Cited By ~ 19

Author(s):

R.G.H. Downer

Keyword(s):

Periplaneta Americana ◽

Fat Body ◽

American Cockroach

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Occurrence of three forms of glycogen phosphorylase and flight-induced enzyme activation in fat body of the american cockroach, Periplaneta americana

Comparative Biochemistry and Physiology Part B Comparative Biochemistry ◽

10.1016/0305-0491(89)90028-x ◽

1989 ◽

Vol 94 (1) ◽

pp. 165-169 ◽

Cited By ~ 1

Author(s):

Wil J.A. Van Marrewuk ◽

Aloys Th.M. Van Den Broek ◽

Ad M.Th. Beenakkers

Keyword(s):

Glycogen Phosphorylase ◽

Periplaneta Americana ◽

Fat Body ◽

Enzyme Activation ◽

American Cockroach

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Isolation and structure of a novel charged member of the red–pigment-concentrating hormone-adipokinetic hormone family of peptides isolated from the corpora cardiaca of the blowfly Phormia terraenovae (Diptera)

Biochemical Journal ◽

10.1042/bj2690309 ◽

1990 ◽

Vol 269 (2) ◽

pp. 309-313 ◽

Cited By ~ 32

Author(s):

G Gäde ◽

H Wilps ◽

R Kellner

Keyword(s):

Periplaneta Americana ◽

Fat Body ◽

Locusta Migratoria ◽

Reversed Phase ◽

American Cockroach ◽

Red Pigment ◽

Adipokinetic Hormone ◽

Migratory Locust ◽

Corpora Cardiaca ◽

Adipokinetic Hormone Family

A hypertrehalosaemic neuropeptide from the corpora cardiaca of the blowfly Phormia terraenovae has been isolated by reversed-phase h.p.l.c., and its primary structure was determined by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal pyroglutamate residue. The C-terminus was also blocked, as indicated by the lack of digestion when the peptide was incubated with carboxypeptidase A. The octapeptide has the sequence pGlu-Leu-Thr-Phe-Ser-Pro-Asp-Trp-NH2 and is clearly defined as a novel member of the RPCH/AKH (red-pigment-concentrating hormone/adipokinetic hormone) family of peptides. It is the first charged member of this family to be found. The synthetic peptide causes an increase in the haemolymph carbohydrate concentration in a dose-dependent fashion in blowflies and therefore is named ‘Phormia terraenovae hypertrehalosaemic hormone’ (Pht-HrTH). In addition, receptors in the fat-body of the American cockroach (Periplaneta americana) recognize the peptide, resulting in carbohydrate elevation in the blood. However, fat-body receptors of the migratory locust (Locusta migratoria) do not recognize this charged molecule, and thus no lipid mobilization is observed in this species.

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Corpus cardiacum stimulated trehalose efflux from cockroach (Periplaneta americana) fat body: control by calcium

Canadian Journal of Zoology ◽

10.1139/z85-012 ◽

1985 ◽

Vol 63 (1) ◽

pp. 63-66 ◽

Cited By ~ 24

Author(s):

J. E. Steele ◽

T. Paul

Keyword(s):

Cyclic Amp ◽

Periplaneta Americana ◽

Saline Solution ◽

Fat Body ◽

Surrounding Medium ◽

Physiological Saline ◽

Corpus Cardiacum ◽

Physiological Saline Solution ◽

Stimulation Of

Cockroach fat body incubated in a simple physiological saline solution releases trehalose to the surrounding medium. The output of trehalose occurs in the absence of ambient Ca2+ and decreases slowly with time. In two separate experiments, 0.1 mM CaCl2 added to the saline increased the output of trehalose on average by 70% but higher concentrations of Ca2+ did not further increase the efflux of trehalose. Stimulation of trehalose efflux by corpus cardiacum extract is absolutely dependent on extracellular Ca2+, no increase occurring beyond the basal level in the absence of the ion. The activity of corpus cardiacum extract increases as the concentration of CaCl2 is increased to 0.5 mM. This concentration of Ca2+ in the saline permits the extract to increase trehalose efflux by as much as 60% above the basal level. Corpus cardiacum extract, as well as the hypertrehalocaemic agents cyclic AMP and theophylline, increase significantly the influx of Ca2+ into fat body in vitro. The basal efflux of trehalose from fat body and that stimulated by corpus cardiacum extract is not dependent on extracellular Mg2+.

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