Proinsulin exhibits a single structure, whereas insulin-like growth factors refold as two disulfide isomers in equilibrium. Native insulin-related growth factor (IGF)-I has canonical cystines (A6-A11, A7-B7, and A20-B19) maintained by IGF-binding proteins; IGF-swap has alternative pairing (A7-A11, A6-B7, and A20-B19) and impaired activity. Studies of mini-domain models suggest that residue B5 (...

The in vitro synthesis of allotypes of b4/b5 offspring obtained from b4/b4 mothers immunized against paternal allotype b5/b5 was studied in comparison to similar offspring that had escaped from suppression and normal heterozygous b4/b5 rabbits. Nocardia water-soluble mitogen-a rabbit B-cell mitogen which is known to induce the differentiation of small lymphocytes into plasma cells and polyclona...

The in vitro incorporation of a well-characterized integral protein cytochrome b5 into membranes of various subcellular organelles was investigated by biochemical and immunochemical methods. Microsomes, peroxisomes, and outer mitochondrial membranes, all containing endogenous cytochrome b5, incorporated large amounts of the hemoprotein in such a way that it was reducible by an inherent NADH cyt...

Cytochrome P450c17 (P450 17A1, CYP17A1) is a critical enzyme in the synthesis of androgens and is now a target enzyme for the treatment of prostate cancer. Cytochrome P450c17 can exhibit either one or two physiological enzymatic activities differentially regulated by cytochrome b5. How this is achieved remains unknown. Here, comprehensive in silico, in vivo and in vitro analyses were undertaken...

Methyl sterol oxidase of microsomal synthesis of cholesterol from lanosterol is a mixed-function oxidase that is dependent upon reduced pyridine nucleotide. The methyl sterol oxidase, as well as NADH-cytochrome c reductase, in intact rat liver microsomes are inhibited by anti-cytochrome b5 immunoglobulin, but NADPH-cytochrome c reductase is not affected. There is a decreased time lag prior to o...

The enzyme CYP17 primarily regulates androgen production by mediating four reactions: conversion of pregnenolone and progesterone to 17-hydroxypregnenolone and 17-hydroxyprogesterone, respectively (17 -hydroxylase activity), followed by conversion of the 17-hydroxylated steroids to dehydroepiandrosterone and androstenedione, respectively (17,20-lyase activity). Most mammalian CYP17 isoforms hav...

In the search for immunoreagents appropriate for the histopathologic diagnosis of malignant B-cell lymphomas in routinely processed paraffin sections, a new monoclonal antibody, Ki-B5, was generated using a high-grade B-cell lymphoma as the immunogene. Ki-B5 is a mouse IgG1/kappa that recognizes five protein fractions of about 84, 82, 55, 48, and 27 Kd after biosynthetic radiolabeling and immun...

Tail-anchored (TA) proteins are membrane proteins that contain an N-terminal domain exposed to the cytosol and a single transmembrane segment near the C-terminus followed by few or no polar residues. TA proteins with a mildly hydrophobic transmembrane domain, such as cytochrome b5 (b5), are able to insert post-translationally into pure lipid vesicles without assistance from membrane proteins. H...

The finitude and environmental impact of petroleum fuels have led to the search alternative biodiesel has proven be an fuel petro-diesel with less impact. Engine performance exhaust emissions Sandbox Methyl Ester (SBME) were evaluated. Pure SBME (B100) was blended diesel at 5, 10, 15, 20, 25 50% volume designated B5, B10, B15, B20, B25 B50 respectively. used as a reference fuel. blends (B100-B5...

Microsomal cytochrome b5 was 352-fold purified from potato tubers with a yield of 10.4%. To our knowledge, this is the first report relating the purification of higher-plant cytochrome b5. Its Mr (16 700) and absorption spectrum are similar to those of animal and yeast cytochrome b5.