کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5915997 | 1570659 | 2008 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
A family of cathepsin B cysteine proteases expressed in the gut of the human hookworm, Necator americanus
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شناسی مولکولی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: A family of cathepsin B cysteine proteases expressed in the gut of the human hookworm, Necator americanus A family of cathepsin B cysteine proteases expressed in the gut of the human hookworm, Necator americanus](/preview/png/5915997.png)
چکیده انگلیسی
mRNAs encoding cathepsin B-like cysteine proteases (CatBs) are abundantly expressed in the genomes of blood-feeding nematodes. Recombinant CatBs have been partially efficacious in vaccine trials in animal models of hookworm infection, supporting further investigation of these enzymes as new control tools. We recently described a family of four distinct CatBs (Na-CP-2, -3, -4, -5) from the human hookworm, Necator americanus. Here we show that these N. americanus CatBs form a robust clade with other hookworm CatBs and are most similar to intestinal CatBs from Haemonchus contortus. All four mRNAs (Na-cp-2, -3, -4 and -5) are up-regulated during the transition from a free-living larva to a blood-feeding adult worm and are also expressed in gut tissue of adult N. americanus that was dissected using laser microdissection microscopy. Recombinant Na-CP-3 was expressed in soluble, secreted form in the yeast Pichia pastoris, while Na-CP-2, -4 and -5 were expressed in insoluble inclusion bodies in Escherichia coli. Recombinant Na-CP-3 was not catalytically active when secreted by yeast but underwent auto-activation to an active enzyme at low pH in the presence of dextran sulphate. Activated Na-CP-3 digested gelatin and cleaved the fluorogenic substrate Z-Phe-Arg-aminomethylcoumarin (AMC) but not Z-Arg-Arg-AMC. Recombinant Na-CP-3 did not digest intact hemoglobin but digested globin fragments generated by prior hydrolysis with N. americanus aspartic hemoglobinases. Antibodies raised in mice to all four recombinant proteins showed minimal cross-reactivity with each other, and each antiserum bound to the intestine of adult N. americanus, supporting the intestinal expression of their mRNAs. These data show that N. americanus expresses a family of intestinal CatBs, many of which are likely to be involved in nutrient acquisition and therefore are potential targets for chemotherapies and vaccines.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Molecular and Biochemical Parasitology - Volume 160, Issue 2, August 2008, Pages 90-99
Journal: Molecular and Biochemical Parasitology - Volume 160, Issue 2, August 2008, Pages 90-99
نویسندگان
Najju Ranjit, Bin Zhan, Deborah J. Stenzel, Jason Mulvenna, Ricardo Fujiwara, Peter J. Hotez, Alex Loukas,