Through controlled synthesis and molecular assembly, biological systems are able to organize molecules into supramolecular structures that carry out sophisticated processes. Although chemists have reported a few examples of supramolecular assembly in water, the controlled covalent synthesis of large molecules and structures in vivo has remained challenging. Here we report a condensation reactio...

An extracellular nuclease produced by Staphylococcus aureus1-3 has been shown to contain 149 amino acid residues (mol wt, 16,807) and to lack both sulfhydryl groups and disulfide bonds (Fig. 1).3-5 The enzyme catalyzes the cleavage of both DNA and RNA to yield 3’-nucleotides.2s 3 The absolute requirement for Ca++ l* 2s 6 may be explained by the interdependency of Gaff and nucleotide binding to ...

Npro is a key effector protein of pestiviruses such as bovine viral diarrhea virus and abolishes host cell antiviral defense mechanisms. Synthesized as the N-terminal part of the viral polyprotein, Npro releases itself via an autoproteolytic cleavage, triggering its immunological functions. However, the mechanisms of its proteolytic action and its immune escape were unclear. Here, we present th...

We used recombinant DNA technology to construct a mutant form of Pseudomonas exotoxin A (PE) called cysPE35 that contains amino acids 280-364 and 381-613 of PE. cysPE35 begins at the native PE proteolytic cleavage site and contains a single cysteine residue at position 287 that can be used to conjugate the toxin to monoclonal antibodies (MAbs). Unlike immunotoxins containing larger mutant forms...

The premature GDF/PDF/MIC-1 protein consists of 308 amino acids that contain a 29 amino acid signal peptide, a 167 amino acid propeptide, and a 112 amino acid mature protein. The mature protein is secreted as a homodimer linked by disulfide bonds and is released from the propeptide following intracellular cleavage at RXXR furine-like cleavage site. The mature peptide of GDF-1/MIC-1 contains two...

Human high molecular weight kininogen (HMWK). a singlechain protein with mol wt 120.000. is cleaved by human urinary kallikrein (HUK) to release kinin from within a disulfide loop and form a two-chain protein that retains all the procoagulant activity of the native molecule. Cleavage of HMWK by HUK is associated with a reduction in size to mol wt 1 1 5.000. as assessed by SDS-PAGE of unreduced ...

Human high molecular weight kininogen (HMWK). a singlechain protein with mol wt 120.000. is cleaved by human urinary kallikrein (HUK) to release kinin from within a disulfide loop and form a two-chain protein that retains all the procoagulant activity of the native molecule. Cleavage of HMWK by HUK is associated with a reduction in size to mol wt 1 1 5.000. as assessed by SDS-PAGE of unreduced ...

Arterial thrombi and atherosclerotic lesions were analyzed immunochemically and examined histologically. The extent of in vivo proteolytic cleavage of the amino-terminal end of fibrinogen by thrombin and plasmin was determined and quantitated by specific radioimmunoassays. The samples were treated with cyanogen bromide (CNBr). and the total amount of fibrinogen and fibrin-derived protein was de...