Publication Date:
1992-12-18
Description:
The parasitic nematode Ascaris infests a billion people worldwide. Much of its proliferative success is due to prodigious egg production, up to 10(6) sterol-replete eggs per day. Sterol synthesis requires molecular oxygen for squalene epoxidation, yet oxygen is scarce in the intestinal folds the worms inhabit. Ascaris has an oxygen-avid hemoglobin in the perienteric fluid that bathes its reproductive organs. Purified hemoglobin contained tightly bound squalene and functioned as an NADPH-dependent, ferrihemoprotein reductase. All components of the squalene epoxidation reaction--squalene, oxygen, NADPH, and NADPH-dependent reductase--are assembled on the hemoglobin. This molecule may thus function in sterol biosynthesis.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sherman, D R -- Guinn, B -- Perdok, M M -- Goldberg, D E -- AM-20579/AM/NIADDK NIH HHS/ -- RR-00954/RR/NCRR NIH HHS/ -- New York, N.Y. -- Science. 1992 Dec 18;258(5090):1930-2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Medicine, Washington University School of Medicine, St. Louis, MO.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1470914" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Ascaris/*metabolism
;
Hemoglobins/*metabolism
;
Kinetics
;
Mass Spectrometry
;
NADPH-Ferrihemoprotein Reductase/metabolism
;
Oxyhemoglobins/*metabolism
;
Squalene/metabolism
;
Sterols/*biosynthesis/isolation & purification
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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