Adenylate kinase from baker's yeast. II. Substrate specificity

Su, Shirley; Russell, Percy J.

doi:10.1016/0005-2744(67)90156-8

Cited by 30 publications

(7 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…OTFP (100 M) reduced JHDK activity by 25%, similar to iodoacetamide, likely due to its highly nucleophilic trifluoromethyl ketone moiety. Taken together, these observations support a mechanism of inhibition similar to that for adenylate kinase (29) in which partial inhibition by reducing agents is attributed to a lone Cys residue not associated with the active site. The detergents Tween and Triton X-100 each showed significant inhibition of JHDK activity at relatively low concentrations, supporting the hypothesis that a homodimer is required for activity.…”

Section: Fig 3 Rplc Purification Of Jhdk By Wax Chromatographysupporting

confidence: 66%

Juvenile Hormone Diol Kinase

Maxwell

Welch

Schooley

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

Manduca sexta juvenile hormone diol kinase (JHDK) catalyzes the conversion of juvenile hormone (JH) diol to JH diol phosphate. JHDK may be the first example of a phosphotransferase directly involved in the catabolism and inactivation of a lipid-soluble hormone. JHDK is an enzyme crucial for secondary metabolism of JH and possesses high specificity and catalytic efficiency for JH diol. In this study, the purification and characterization of native JHDK are described; its enzymatic properties are examined; and its role in cellular JH metabolism is explored. Using a variety of potential substrates, we show that JHDK has a preference for ATP, but will catalyze the formation of JH diol phosphate with GTP as the phosphate donor. JHDK has a nanomolar K m for JH I diol and a low micromolar value for MgATP. JH II and III diols also serve as phosphate acceptors with low micromolar K m , whereas other diol derivatives of terpenoid esters structurally similar to JH metabolites are not phosphorylated. The reaction proceeds via a sequential Bi Bi mechanism. JHDK is active as a homodimer with a subunit molecular mass of 20 kDa. JHDK binds 5-p-fluorosulfonylbenzoyladenosine and is inhibited by micromolar levels of Ca 2؉ .Juvenile hormones (compound 1; see Fig. 7) are sesquiterpenoids produced in the corpora allata of insects. They travel to target tissues through the hemolymph via a juvenile hormone (JH) 1 -binding protein, where they serve to modulate development, metamorphosis, and sexual maturation (1). During metamorphosis and larval development, JH titers are strictly regulated through biosynthesis and catabolism (2, 3). JH esterase (JHE) and JH epoxide hydrolase are regarded as the enzymes responsible for JH catabolism. However, recent studies have identified a hormonal role for JH acid (compound 2; see Fig. 7) (4, 5), suggesting that JHE is more than an inactivating enzyme. Recently, a cytochrome P450 terpenoid hydroxylase was discovered in the corpora allata of Diploptera punctata; this enzyme may play a role in the temporal suppression of JH titer in the cockroach by metabolizing JH III to 12-hydroxy-JH III (6).Most identifications of JH metabolites in the past have involved studies using either hemolymph or whole organisms, making it difficult to distinguish the role of intracellular JH metabolism. Two studies have been conducted using Manduca sexta tissues dissected and maintained in vitro, one with Malpighian tubules (7) and the other with fat body and imaginal discs (8). The classic model for JH metabolism in insects consists of two primary pathways of inactivation: epoxide hydrolysis to form the diol metabolites and ester cleavage to form the acid metabolites. However, there have been many reports indicating very polar JH metabolites (9 -15). We identified and characterized JH diol phosphate (JHDP; compound 11; Fig. 1), one such polar metabolite, and suggested that it is the principal end product of JH I metabolism in M. sexta (11).We isolated and characterized JH diol kinase (JHDK) from the Malpighian tubules o...

show abstract

Section: Fig 3 Rplc Purification Of Jhdk By Wax Chromatographysupporting

confidence: 66%

Juvenile Hormone Diol Kinase

Maxwell

Welch

Schooley

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…The affinity of an active center for AMP is independent of the nucleoside triphosphate concentration, but dependent on its nature. Similar results were reported with other nucleotides on bakers' yeast adenylate kinase (33). It is possible that besides specific interactions, the different nucleotides acting as substrates may influence the adenylate kinase activity through interactions of a different nature.…”

Section: Discussionsupporting

confidence: 77%

“…One also should keep in mind that, besides the real peculiarities of the enzyme under investigation, there are always sources of error due to the degree of purification, the methods used to assay the enzyme activity by coupled reactions, or the purity of commercial or synthesized nucleotides (34). The different adenylate kinases have a common feature, namely their high specificity for AMP as acceptor, while ATP may be replaced by other nucleoside triphosphates (30)(31)(32)(33). The lack of a measurable reaction rate in the forward direction when nucleoside diphosphates other than ADP are used is not definite proof that they are not substrates for adenylate kinase, as claimed by Su and Russell (33).…”

Section: Discussionmentioning

confidence: 83%

“…It is known that the substrate specificity of adenylate kinase differs from one source of enzyme to another (30)(31)(32)(33). One also should keep in mind that, besides the real peculiarities of the enzyme under investigation, there are always sources of error due to the degree of purification, the methods used to assay the enzyme activity by coupled reactions, or the purity of commercial or synthesized nucleotides (34).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Participation of N ₁ -Oxide derivatives of Adenine Nucleotides in the Phosphotransferase Activity of Liver Mitochondria

Jebeleanu¹,

Ty²,

Mantsch³

et al. 1974

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Kinetic studies of yeast adenylate kinase (25) have shown that the reaction is limited by the rate of conversion of the enzyme from E-ADP 2 to E-AMP-ATP. Thus, we were able to assume that the binding steps in the adenylate kinase reaction were at equilibrium.…”

Section: Permeability To Adp/atpmentioning

confidence: 99%

New Insights into the Mechanism of Permeation through Large Channels

Komarov

Deng

Craigen

et al. 2005

Biophysical Journal

View full text Add to dashboard Cite

The mitochondrial channel, VDAC, regulates metabolite flux across the outer membrane. The open conformation has a higher conductance and anionic selectivity, whereas closed states prefer cations and exclude metabolites. In this study five mutations were introduced into mouse VDAC2 to neutralize the voltage sensor. Inserted into planar membranes, mutant channels lack voltage gating, have a lower conductance, demonstrate cationic selectivity, and, surprisingly, are still permeable to ATP. The estimated ATP flux through the mutant is comparable to that for wild-type VDAC2. The outer membranes of mitochondria containing the mutant are permeable to NADH and ADP/ATP. Both experiments support the counterintuitive conclusion that converting a channel from an anionic to a cationic preference does not substantially influence the flux of negatively charged metabolites. This finding supports our previous proposal that ATP translocation through VDAC is facilitated by a set of specific interactions between ATP and the channel wall.

show abstract

Adenylate kinase from baker's yeast. II. Substrate specificity

Cited by 30 publications

References 8 publications

Juvenile Hormone Diol Kinase

Juvenile Hormone Diol Kinase

Participation of N ₁ -Oxide derivatives of Adenine Nucleotides in the Phosphotransferase Activity of Liver Mitochondria

New Insights into the Mechanism of Permeation through Large Channels

Contact Info

Product

Resources

About

Adenylate kinase from baker's yeast. II. Substrate specificity

Cited by 30 publications

References 8 publications

Juvenile Hormone Diol Kinase

Juvenile Hormone Diol Kinase

Participation of N 1 -Oxide derivatives of Adenine Nucleotides in the Phosphotransferase Activity of Liver Mitochondria

New Insights into the Mechanism of Permeation through Large Channels

Contact Info

Product

Resources

About

Participation of N ₁ -Oxide derivatives of Adenine Nucleotides in the Phosphotransferase Activity of Liver Mitochondria