Hostname: page-component-7c8c6479df-hgkh8 Total loading time: 0 Render date: 2024-03-28T21:13:56.902Z Has data issue: false hasContentIssue false

Blood digestion in the mosquito, Anopheles stephensi: the effects of Plasmodium yoelii nigeriensis on midgut enzyme activities

Published online by Cambridge University Press:  16 October 2009

N. JAHAN
Affiliation:
Centre for Applied Entomology and Parasitology, Department of Biological Sciences, Keele University, Staffordshire ST5 5BG Current address: Lahore College for Women, Lahore, Pakistan.
P. T. DOCHERTY
Affiliation:
Department of Zoology, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ Current address: Medical Entomology Section, Laboratory for Parasitic Diseases, NIAID/NIH, Bethesda, MD 20892-0425, USA.
P. F. BILLINGSLEY
Affiliation:
Department of Zoology, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ
H. HURD
Affiliation:
Centre for Applied Entomology and Parasitology, Department of Biological Sciences, Keele University, Staffordshire ST5 5BG

Abstract

Midgut proteases contribute to the success or failure of Plasmodium infection of the mosquito. This paper examines the reciprocal effect of Plasmodium yoelii nigeriensis on midgut trypsin, chymotrypsin, aminopeptidase and carboxypeptidase in the mosquito Anopheles stephensi. The total protein ingested and the rate of protein digestion were unaffected by the parasite, but more protein was ingested at the first than the second bloodmeal. All peptidases were unaffected by the presence of the parasite during the first gonotrophic cycle, when ookinetes were penetrating the midgut. In the second gonotrophic cycle, trypsin and chymotrypsin were unaffected by growing oocysts, but aminopeptidase activity was reduced in the midguts of infected mosquitoes. Chymotrypsin activity was depressed and aminopeptidase activity elevated during the second gonotrophic cycle. Plasmodium infection has a negligible effect on bloodmeal digestion and does not limit the availability of the protein for egg production. The significance of changes in aminopeptidase activity when oocysts are present is discussed.

Type
Research Article
Copyright
© 1999 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)