The first archaeal ATP-dependent glucokinase, from the hyperthermophilic crenarchaeon Aeropyrum pernix, represents a monomeric, extremely thermophilic ROK glucokinase with broad hexose specificity.

ABSTRACT: An ATP-dependent glucokinase of the hyperthermophilic aerobic crenarchaeon Aeropyrum pernix was purified 230-fold to homogeneity. The enzyme is a monomeric protein with an apparent molecular mass of about 36 kDa. The apparent K(m) values for ATP and glucose (at 90 degrees C and pH 6.2) were 0.42 and 0.044 mM, respectively; the apparent V(max) was about 35 U/mg. The enzyme was specific for ATP as a phosphoryl donor, but showed a broad spectrum for phosphoryl acceptors: in addition to glucose, which showed the highest catalytic efficiency (k(cat)/K(m)), the enzyme also phosphorylates glucosamin, fructose, mannose, and 2-deoxyglucose. Divalent cations were required for maximal activity: Mg(2+), which was most effective, could partially be replaced with Co(2+), Mn(2+), and Ni(2+). The enzyme h

SUBMITTER: Hansen T 

PROVIDER: S-EPMC135380 | biostudies-literature | 2002 Nov

REPOSITORIES: biostudies-literature