Ixodes scapularis: salivary kininase activity is a metallo dipeptidyl carboxypeptidase.
Saliva and salivary gland homogenates of Ixodes scapularis contain a dipeptidyl carboxypeptidase activity that accounts for the previously described salivary kininase activity of this tick. Reversed phase HPLC and laser desorption mass spectrography of the reaction products identified bradykinin fragment 1-7 and 1-5 as being produced subsequent to incubation of purified salivary kininase with bradykinin. The activity was inhibited by captopril and EDTA and was activated by cobalt and manganese, a behavior similar to that displayed by angiotensin-converting enzymes of vertebrate and invertebrate origins.
Ribeiro
J M
JM
Section of Medical Entomology, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. JRibeiro@atlas.niaid.nih.gov
Mather
T N
TN
D000803:Angiotensin I / Q000378:metabolism; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D001681:Biological Assay; D001920:Bradykinin / Q000737:chemistry / Q000378:metabolism*; D002216:Captopril / Q000494:pharmacology; D002268:Carboxypeptidases / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003035:Cobalt / Q000494:pharmacology; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000737:chemistry / Q000378:metabolism*; D004492:Edetic Acid / Q000494:pharmacology; D005260:Female; D006168:Guinea Pigs; D006863:Hydrogen-Ion Concentration; D018884:Ixodes / Q000201:enzymology*; D008345:Manganese / Q000494:pharmacology; D008666:Metalloendopeptidases / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D012463:Saliva / Q000201:enzymology; D012469:Salivary Glands / Q000201:enzymology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000806:Angiotensin-Converting Enzyme Inhibitors; D010446:Peptide Fragments; D003035:Cobalt; D008345:Manganese; D000803:Angiotensin I; D004492:Edetic Acid; D002216:Captopril; D002268:Carboxypeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D008666:Metalloendopeptidases; D001920:Bradykinin