Short Peptide Tag for Covalent Protein Labeling Based on Coiled Coils

To label proteins covalently, one faces a trade-off between labeling a protein specifically and using a small tag. Often one must compromise one parameter for the other or use additional components, such as an enzyme, to satisfy both requirements. Here, we report a new reaction that covalently labels proteins by using engineered coiled-coil peptides. Harnessing the concept of “proximity-induced reactivity”, the 21-amino-acid three-heptad peptides CCE/CCK were modified with a nucleophilic cysteine and an α-chloroacetyl group at selected positions. When pairs of coiled coils associated, an irreversible covalent bond spontaneously formed between the peptides. The specificity of the cross-linking reaction was characterized, the probes were improved by making them bivalent, and the system was used to label a protein <i>in vitro</i> and receptors on the surface of mammalian cells

The process of ZigBee Ad-hoc network.

<p>The process of ZigBee Ad-hoc network.</p

The server program workflow.

<p>The server program workflow.</p

ZigBee network routing layout after simulation.

<p>ZigBee network routing layout after simulation.</p

GA-PSOA computational flow chart.

<p>GA-PSOA computational flow chart.</p

A flow chart from Android APP program.

<p>A flow chart from Android APP program.</p

The framework of the system.

<p>The framework of the system.</p

End-to-end delay.

<p>End-to-end delay.</p

The ZigBee event handling process.

<p>The ZigBee event handling process.</p

The server connection process.

<p>The server connection process.</p