ISOLATION OF NON-IDENTICAL POLYPEPTIDE CHAINS OF α-CRYSTALLIN

The formation of amyloid aggregates is a feature of most, if not all, polypeptide chains. In vivo modelling of this process has been undertaken in the fruitfly Drosophila melanogaster with remarkable success. Models of both neurological and systemic amyloid diseases have been generated and have informed our understanding of disease pathogenesis in two main ways. First, the toxic amyloid species have been at least partially characterized, for example in the case of the Aβ (amyloid β-peptide) associated with Alzheimer's disease. Secondly, the genetic underpinning of model disease-linked phenotypes has been characterized for a number of neurodegenerative disorders. The current challenge is to integrate our understanding of disease-linked processes in the fly with our growing knowledge of human disease, for the benefit of patients.

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Common Antigenic Sites in Human, Bovine and Porcine Fibrinogens

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650157 ◽

1981 ◽

Vol 45 (02) ◽

pp. 169-172 ◽

Cited By ~ 2

Author(s):

Czeslaw S Cierniewski

Keyword(s):

Antigenic Determinants ◽

Antigenic Sites ◽

Specific Antisera ◽

Antigenic Homology ◽

Polypeptide Chains ◽

Fibrinogen Molecule

SummarySpecific antisera to the Aα, Bβ and γ chains of porcine fibrinogen were used to characterize an antigenic homology of human, bovine, and porcine fibrinogens. Antigenic determinants shared by these fibrinogens were mostly formed by the Aα chain. However, in the case of bovine and porcine fibrinogens they were also found in the Bβ and γ polypeptide chains. The results reported here show that the Aα chain determinants exposed on the intact fibrinogen molecule are conserved to a considerably larger extent than those of the Bβ and γ chains.

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Sialic Acid Dependent Polypeptide Chain Heterogeneity of Human Fibrinogen Demonstrated by Two-Dimensional Electrophoresis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657116 ◽

1982 ◽

Vol 47 (01) ◽

pp. 019-021 ◽

Cited By ~ 13

Author(s):

Cemal Kuyas ◽

André Haeberli ◽

P Werner Straub

Keyword(s):

Sialic Acid ◽

Polypeptide Chain ◽

Two Dimensional ◽

Charge Heterogeneity ◽

Human Fibrinogen ◽

Two Dimensional Electrophoresis ◽

Isoelectric Points ◽

Polypeptide Chains ◽

Dimensional Electrophoresis ◽

Chain Type

SummaryHuman fibrinogen was compared with asialofibrinogen by two-dimensional electrophoresis to evaluate the contribution of sialic acid to the heterogeneity of the γ- and Bβ-polypeptide chains.Reduced fibrinogen showed three major variants for both the γ- and Bβ-chains. In addition two minor γ-bands with a more acidic isoelectric point than the normal γ-chains were observed. Electrophoresis in the second dimension (SDS) suggests that these most acidic bands are γ-chain-variants with a higher molecular weight. In asialofibrinogen only two predominant variants with more alkaline isoelectric points were present in each chain type.It is concluded that enzymatic removal of sialic acid partially reduces the heterogeneity of the γ- and Bβ-polypeptide chains of human fibrinogen, but additional sources producing charge heterogeneity must be sought.

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m-[o-(2-Chloro-5-Fluorosulfonylphenylureido)Phenoxybutoxy]Benzamidine: Affinity Labeling Reagent Which Can Identify Secondary Binding Sites of Coagulation Complement and Fibrinolytic Serine Proteases

10.1055/s-0038-1665767 ◽

1979 ◽

Author(s):

D Bing ◽

D Robison ◽

J Andrews ◽

R Laura

Keyword(s):

Binding Sites ◽

Serine Proteases ◽

Enzyme Inhibitor ◽

Molecular Model ◽

Factor Xa ◽

Affinity Labeling ◽

Catalytic Center ◽

Inhibitor Complex ◽

Polypeptide Chains ◽

Kinetics Of

We have determined that m-[o-(2-chloro-5-fluorosulfonylphenylureido)phenoxybutoxy]benza-midine [mCP(PBA)-F] is an affinity labeling reagent which labels both polypeptide chains of thrombin, factor Xa, complement component CIS and plasmin. As this means it is reacting outside of the catalytic center, we have called this reagent an exo-site affinity labeling reagent. Progressive irreversible inhibition of these enzymes by this reagent is rapid (k1st 2.5-4.6 x 10-3sec-1), the kinetics of inactivation are consistent with inhibition proceding via formation of a specific enzyme-inhibitor complex analogous to a Michaelis-Menton complex (KL - 115-26 μM), and diisopropylfluorophosphate or p-amidino-phenylmethanesulfonyfluoride Prevent labeling by [3H]mCP(PBA)-F. A molecular model of mCP(PBA)-F shows that the reactive SO2F group can be 17 A from the cationic amidine. The data are consistent with the hypothesis that both peptide chains are required for the specific proteolytic activity exhibited by these proteases and that the peptide chain which does not contain the active site serine is close to the catalytic center. (Supported by NIH and AHA grants

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Alignment of Rigid-Rod Polypeptide Chains by Solvent Quenching

MRS Proceedings ◽

10.1557/proc-771-l10.23 ◽

2003 ◽

Vol 771 ◽

Author(s):

Yuli Wang ◽

Ying Chih Chang

Keyword(s):

Tilt Angle ◽

Rigid Rod ◽

Polypeptide Chains ◽

Poor Solvent

AbstractWe introduce a simple “solvent quenching” approach to align the rigid-rod à-helical poly(α-benzyl-L-glutamate) (PBLG) chains in the surface-grafted monolayer. By sequentially treating with a good solvent and a poor solvent, a unidirectionally aligned PBLG monolayer with an average tilt angle as small as 3° is obtained.

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