Stephen Perkins

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Amino acid sequences, carbohydrate compositions and residue volumes are used to compare critically calculations of partial specific volumes v, neutron scattering matchpoints and 280-nm absorption coefficients with experimental v values for proteins and glycoproteins. The v values that are obtained from amino acid densitometry underestimate experimental v(More)
Solution scattering is a low resolution diffraction method that provides important structural data on proteins. The ability to model scattering curves by recourse to known crystal structures for proteins under study significantly improves the resolution (and the utility) of the method because of the strict constraints that the crystal structures impose. For(More)
Human immunoglobulin A (IgA) is an abundant antibody that mediates immune protection at mucosal surfaces as well as in plasma. The IgA1 isotype contains two four-domain Fab fragments and a four-domain Fc fragment analogous to that in immunoglobulin G (IgG), linked by a glycosylated hinge region made up of 23 amino acid residues from each of the heavy(More)
We describe a family with autosomal dominant inheritance of increased body iron stores characterized by raised serum ferritin concentration and normal transferrin saturation. Liver biopsy showed iron deposition in Kupffer cells without fibrosis. The clinical features of HFE-related hemochromatosis were absent, as were the Cys282Tyr and His63Asp mutations.(More)
We report a novel pathomechanism for membranoproliferative glomerulonephritis type II (MPGN II) caused by a mutant Factor H protein expressed in the plasma. Genetic analyses of two patients revealed deletion of a single Lys residue (K224) located within the complement regulatory region in domain 4 of Factor H. This deletion resulted in defective complement(More)
Factor H (FH) is a central complement regulator comprised of 20 short complement repeat (SCR) domains. Nucleotide changes within this gene (CFH) have been observed in patients with hemolytic uremic syndrome (HUS), and also membranoproliferative glomerulonephritis and age-related macular degeneration. All parts of FH are affected, but many mutations are(More)
BACKGROUND Factor IX (FIX) is important in the coagulation cascade, being activated to FIXa on cleavage. Defects in the human F9 gene frequently lead to hemophilia B. OBJECTIVE To assess 1113 unique F9 mutations corresponding to 3721 patient entries in a new and up-to-date interactive web database alongside the FIXa protein structure. METHODS The(More)
Human immunoglobulin E (IgE) consists of 14 domains, each with the characteristic immunoglobulin fold structure. Compared with the 12-domain structure of immunoglobulin G (IgG), IgE has an additional pair of domains (C epsilon 2) in the Fc region in place of the hinge of IgG. The crystal structure of the 4-domain Fc fragment of IgG is known, but not that of(More)
Anosmin-1, the gene product of the KAL gene, is implicated in the pathogenesis of X-linked Kallmann's syndrome. Anosmin-1 protein expression is restricted to the basement membrane and interstitial matrix of tissues affected in this syndrome during development. The anosmin-1 sequence indicates an N-terminal cysteine-rich domain, a whey acidic protein (WAP)(More)
The large multidomain muscle protein myosin binding protein C (MyBP-C) has been implicated for some time in cardiac disease while until recently little was known about its structure and function. Here we present a detailed study of the central domain C5 of the cardiac isoform of MyBP-C. This domain is unusual in several aspects. Firstly it contains two(More)