TY - JOUR
T1 - X-ray crystallography and NMR studies of domain-swapped canecystatin-1
AU - Valadares, Napoleão F.
AU - De Oliveira-Silva, Rodrigo
AU - Cavini, Italo A.
AU - De Almeida Marques, Ivo
AU - D'Muniz Pereira, Humberto
AU - Soares-Costa, Andrea
AU - Henrique-Silva, Flavio
AU - Kalbitzer, Hans R.
AU - Munte, Claudia E.
AU - Garratt, Richard C.
PY - 2013/2
Y1 - 2013/2
N2 - The three-dimensional structure of canecystatin-1, a potent inhibitor of cysteine proteases from sugarcane (Saccharum officinarum), has been solved in two different crystal forms. In both cases, it is seen to exist as a domain-swapped dimer, the first such observation for a cystatin of plant origin. Size exclusion chromatography and multidimensional NMR spectroscopy show the dimer to be the dominant species in solution, despite the presence of a measurable quantity of monomer undergoing slow exchange. The latter is believed to be the active species, whereas the domain-swapped dimer is presumably inactive, as its first inhibitory loop has been extended to form part of a long β-strand that forms a double-helical coiled coil with its partner from the other monomer. A similar structure is observed in human cystatin C, but the spatial disposition of the two lobes of the dimer is rather different. Dimerization is presumably a mechanism by which canecystatin-1 can be kept inactive within the plant, avoiding the inhibition of endogenous proteases. The structure described here provides a platform for the rational design of specific cysteine protease inhibitors for biotechnological applications.
AB - The three-dimensional structure of canecystatin-1, a potent inhibitor of cysteine proteases from sugarcane (Saccharum officinarum), has been solved in two different crystal forms. In both cases, it is seen to exist as a domain-swapped dimer, the first such observation for a cystatin of plant origin. Size exclusion chromatography and multidimensional NMR spectroscopy show the dimer to be the dominant species in solution, despite the presence of a measurable quantity of monomer undergoing slow exchange. The latter is believed to be the active species, whereas the domain-swapped dimer is presumably inactive, as its first inhibitory loop has been extended to form part of a long β-strand that forms a double-helical coiled coil with its partner from the other monomer. A similar structure is observed in human cystatin C, but the spatial disposition of the two lobes of the dimer is rather different. Dimerization is presumably a mechanism by which canecystatin-1 can be kept inactive within the plant, avoiding the inhibition of endogenous proteases. The structure described here provides a platform for the rational design of specific cysteine protease inhibitors for biotechnological applications.
KW - domain-swapped
KW - NMR
KW - phytocystatin
KW - X-ray crystallography
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U2 - 10.1111/febs.12095
DO - 10.1111/febs.12095
M3 - Article
C2 - 23241243
AN - SCOPUS:84874105057
SN - 1742-464X
VL - 280
SP - 1028
EP - 1038
JO - FEBS Journal
JF - FEBS Journal
IS - 4
ER -