MTS
(methanethiosulfonate) reagents were first developed by Dr. Arthur
Karlin and colleagues as powerful tools to probe the structures and
functions of proteins, particularly membrane proteins such as ion
channels. The reagents selectively and rapidly react with thiols (sulfhydryls)
to form a disulfide bond and as a result are highly efficient labeling
agents for cysteine residues in proteins.
The so-called SCAM method (substituted-cysteine
accessibility method) employs a combination of chemical and genetic
approaches. First, cysteine residues are systematically introduced at
various positions in a protein via site-directed mutagenisis. Then the
introduced cysteines are assessed on their reactivity and accesibility
toward various MTS reagents. Determination is also made on the effect of
the labeled cysteine on protein function. By using a series of MTS
reagents differing in charge or size of the reagents, SCAM can yield
information on the physical size and electrostatic potential of an ion
channel, and on the membrane-sidedness and accessibility (buried or
exposed) of a residue.
Gentaur proposes a range of MTS
reagents, including the commonly used small, charged and neutral MTS
reagents for SCAM studies as well as fluorescent and biotinyl MTS
derivatives. Fluorescent MTS reagents are useful for real-time studies
of protein structure dynamics by measuring environment-dependent
fluorescence, fluorescence lifetime or fluorescence resonance energy
transfer (FRET). Our biotinyl MTS reagents should find applications in
biotin/avidin chemistry-related studies.We are rapidly expanding our MTS
product line. For updated information on these products, please check
our website. We welcome your suggestions on any new products and the
opportunity to collaborate with you.
