4JAX

Crystal structure of dimeric KlHxk1 in crystal form X

Summary for 4JAX

• Entry DOI: 10.2210/pdb4jax/pdb
• Related: 3O08 3O1B 3O1W 3O4W 3O5B 3O6W 3O80 3O8M 4JB1
• Descriptor: Hexokinase, PHOSPHATE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: ribonuclease h-fold, transferase, hexokinase, atp binding, sugar binding, mig1 binding, phosphorylation
• Biological source: Kluyveromyces lactis (Yeast)
• Total number of polymer chains: 6
• Total formula weight: 324863.52

Authors

Kuettner, E.B.,Strater, N.,Kettner, K.,Otto, A.,Lilie, H.,Golbik, R.P.,Kriegel, T.M. (deposition date: 2013-02-19, release date: 2013-05-01, Last modification date: 2024-10-09)

Primary citation

Kettner, K.,Kuettner, E.B.,Otto, A.,Lilie, H.,Golbik, R.P.,Strater, N.,Kriegel, T.M.
In vivo phosphorylation and in vitro autophosphorylation-inactivation of Kluyveromyces lactis hexokinase KlHxk1.
Biochem.Biophys.Res.Commun., 435:313-318, 2013

PubMed Abstract: The bifunctional hexokinase KlHxk1 is a key component of glucose-dependent signal transduction in Kluyveromyces lactis. KlHxk1 is phosphorylated in vivo and undergoes ATP-dependent autophosphorylation-inactivation in vitro. This study identifies serine-15 as the site of in vivo phosphorylation and serine-157 as the autophosphorylation-inactivation site. X-ray crystallography of the in vivo phosphorylated enzyme indicates the existence of a ring-shaped symmetrical homodimer carrying two phosphoserine-15 residues. In contrast, small-angle X-ray scattering and equilibrium sedimentation analyses reveal the existence of monomeric phosphoserine-15 KlHxk1 in solution. While phosphorylation at serine-15 and concomitant homodimer dissociation are likely to be involved in glucose signalling, mechanism and putative physiological significance of KlHxk1 inactivation by autophosphorylation at serine-157 remain to be established.

PubMed: 23583397
DOI: 10.1016/j.bbrc.2013.03.121

Experimental method

X-RAY DIFFRACTION (2.26 Å)