Chapter 10- CMB

Many cellular proteins are regulated by the level of phosphorylation of certain amino acids. The level of phosphorylation results from the opposing actions of two types of enzymes, protein _______ and protein _______.

A protein kinase transfers a phosphate group from _______ to a protein.

Monomeric G proteins, such as Ras and several elongation factors, are usually in the active state when a molecule of _______ is bound to them

• GDP

• GTP

• ADP

• ATP

Nitrosylation occurs on the side chain of

• lysine

• cysteine

• tyrosine

• serine and threonine

Proteins are often regulated by phosphorylation, which is catalyzed by enzymes called

• protein phosphatases

• phosphoproteases

• protein phosphorylases

• protein kinases

Which of the following amino acids is not commonly phosphorylated to regulate protein activity?

• serine

• threonine

• tryptophan

• tyrosine

The removal of phosphates from proteins is catalyzed by

• protein phosphatases

• phosphoproteases

• protein phosphorlases

• protein kinases

Receptor tyrosine kinases catalyze the transfer of a phosphate group from _______ to the side chains of tyrosine residues.

• cAMP

• the plasma membrane

• ATP

• GTP

. Receptor tyrosine kinases catalyze the transfer of a phosphate group from _______ to the side chains of tyrosine residues.

• growth hormone

• insulin

• steroid hormones

• epinephrine

Which protein is inhibited when bound to its regulatory subunit(s) but becomes active when free?

• adenylyl cyclase

• cAMP-dependent protein kinase

• protein kinase

• phosphorylase kinase