Blood-sucking insect

The Nitric Oxide-Releasing Heme Proteins from the Saliva of the Blood-Sucking Insect Rhodnius prolixus F. Ann Walker and William R. Montfort... 

The specific solvation of NO coordinated to Fe(III) and the resulting solvent reorganization upon NO dissociation (Fig. 3) finds some analogy with the nitrophorins, which are heme protein systems for NO transfer found in certain blood sucking insects. The crystal structure of one nitro-phorin, NP4, shows that binding of NO to the Fe(III) center leads to a collapse of the protein around the coordinated NO. The distal hemebinding pocket in nitrophorin NP4 is quite open to solvent in the absence of NO. It was postulated that collapse of the protein around the heme nitrosyl led to increased retention of bound NO at low pH (25). 

THE NITRIC OXIDE-RELEASING HEME PROTEINS FROM THE SALIVA OF THE BLOOD-SUCKING INSECT Rhodnius prolixus... 

Blood-sucking insects have in their saliva a number of agents that are designed to help them obtain a sufficient blood meal. These substances... 

Trichomoniasis. Infection by protozoa usually affecting the genitourinary system. Trypanosomiasis. Infection of the blood of man or animals in tropical countries by protozoa transmitted by blood sucking insects. Examples are African sleeping sickness and Chagas disease. Trypanocide a drug for the treatment of trypanosomiasis. Vasomotor relaxation. Relaxation of the walls of blood vessels. 

Boulanger, N Munks, R.J., Hamilton, J.V., et al. (2002) Epithelial innate immunity. A novel antimicrobial peptide with antiparasitic activity in the blood-sucking insect Stomoxys calcitrans. J. Biol. Chem. 277(51), 49921 19926. 

F. A. Walker and W. R. Montfort, The Nitric Oxide-Releasing Heme Proteins from the Saliva of the Blood-Sucking Insect Rhodniusprolixus, in Advances in Inorganic Chemistry , eds. A. G. Mauk and A. G. Sykes, Academic Press, San Diego, CA, 2001, Vol. 51, Chap. 5, p. 295. 

Newkirk, M.M., Downe, A.E.R., Simon, J.B. Fate of ingested hepatitis 245. B antigen in blood-sucking insects. Gastroenterology 1975 69 ... 

The NO-binding Nitrophorin 1 (NP1), from the saliva of the blood-sucking insect Rhodnius prolixus, contains two diamagnetic FeNO 6 ferrihemes, with i/NO at 1,904 cm-1 and 1,917 cm-1. They exist in a pH-dependent ratio and bind NO reversibly without being reduced. Alternative electronic distribution assignments as FemNO or FenNO+ rely on IR, EPR, NMR, FTIR, and... 

This is another major protozoal disease of domestic animals prevalent primarily in tropical Africa. The infection is mainly transmitted by tsetse flies, though salivarian or stercoranian methods of infection are also known. Some blood sucking insects such as Tabanus and Stomoxys flies, and also vampire bats may transmit trypanosomiasis in animals. Infections with Trypanosoma equiperdum in horses and donkeys may also be transmitted during coitus. 

Nitrophorins are haem proteins which are present in the salivary glands of the blood-sucking insect Rhodnius prolixus. Binding of NO to the Fe(III) centre in nitrophorin (NPl) is reversible, and is dependent on pH. Crucial to the process of blood-sucking by Rhodnius prolixus is the fact that NO binds 10 times more tightly at pH 5 (i.e. the pH of the saliva... 

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