TY - JOUR
T1 - Inhibition of serine proteinases plasmin, trypsin, subtilisin A, cathepsin G, and elastase by LEKTI
T2 - A kinetic analysis
AU - Mitsudo, Kenji
AU - Jayakumar, Arumugam
AU - Henderson, Ying
AU - Frederick, Mitchell J.
AU - Kang, Ya'an
AU - Wang, Mary
AU - El-Naggar, Adel K.
AU - Clayman, Gary L.
PY - 2003/4/8
Y1 - 2003/4/8
N2 - The human LEKTI gene encodes a putative 15-domain serine proteinase inhibitor and has been linked to the inherited disorder known as Netherton syndrome. In this study, human recombinant LEKTI (rLEKTI) was purified using a baculovirus/insect cell expression system, and the inhibitory profile of the full-length rLEKTI protein was examined. Expression of LEKTI in Sf9 cells showed the presence of disulfide bonds, suggesting the maintenance of the tertiary protein structure. rLEKTI inhibited the serine proteinases plasmin, subtilisin A, cathepsin G, human neutrophil elastase, and trypsin, but not chymotrypsin. Moreover, rLEKTI did not inhibit the cysteine proteinase papain or cathepsin K, L, or S. Further, rLEKTI inhibitory activity was inactivated by treatment with 20 mM DTT, suggesting that disulfide bonds are important to LEKTI function. The inhibition of plasmin, subtilisin A, cathepsin G, elastase, and trypsin by rLEKTI occurred through a noncompetitive-type mechanism, with inhibitory constants (Ki) of 27 ± 5, 49 ± 3, 67 ± 6, 317 ± 36, and 849 ± 55 nM, respectively. Thus, LEKTI is likely to be a major physiological inhibitor of multiple serine proteinases.
AB - The human LEKTI gene encodes a putative 15-domain serine proteinase inhibitor and has been linked to the inherited disorder known as Netherton syndrome. In this study, human recombinant LEKTI (rLEKTI) was purified using a baculovirus/insect cell expression system, and the inhibitory profile of the full-length rLEKTI protein was examined. Expression of LEKTI in Sf9 cells showed the presence of disulfide bonds, suggesting the maintenance of the tertiary protein structure. rLEKTI inhibited the serine proteinases plasmin, subtilisin A, cathepsin G, human neutrophil elastase, and trypsin, but not chymotrypsin. Moreover, rLEKTI did not inhibit the cysteine proteinase papain or cathepsin K, L, or S. Further, rLEKTI inhibitory activity was inactivated by treatment with 20 mM DTT, suggesting that disulfide bonds are important to LEKTI function. The inhibition of plasmin, subtilisin A, cathepsin G, elastase, and trypsin by rLEKTI occurred through a noncompetitive-type mechanism, with inhibitory constants (Ki) of 27 ± 5, 49 ± 3, 67 ± 6, 317 ± 36, and 849 ± 55 nM, respectively. Thus, LEKTI is likely to be a major physiological inhibitor of multiple serine proteinases.
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U2 - 10.1021/bi027029v
DO - 10.1021/bi027029v
M3 - Article
C2 - 12667078
AN - SCOPUS:0037426357
SN - 0006-2960
VL - 42
SP - 3874
EP - 3881
JO - Biochemistry
JF - Biochemistry
IS - 13
ER -