The kinetic mechanism of the unidirectional
H2-oxidizing hydrogenase from soybean nodule bacteroids has
been investigated with highly purified enzyme. Measurements
of the K, for H2 vary from 0.97 to 2.6 pM, and the K,,, for
methylene blue varies from 6 to 17 pM. With H2 and
methylene blue as substrates,...
Carbonyl sulfide (COS) has been investigated as a rapid-equilibrium inhibitor of CO oxidation
by the CO dehydrogenase purified from Rhodospirillum rubrum. The kinetic evidence suggests that the
inhibition by COS is largely competitive versus CO (Ki = 2.3 pM) and uncompetitive versus methylviologen
as electron acceptor (Ki = 15.8 pM)....
The virus-encoded proteins of tobacco etch virus (TEV), a plant potyvirus, arise by proteolytic processing of
a large polyprotein precursor. The TEV genome codes for two proteinases, a 49-kilodalton proteinase and
helper component proteinase (HC-Pro), which cleave the polyprotein at specific sites. The only known cleavage
event catalyzed by HC-Pro...