Abstract
Glucose phosphorylating enzymes are crucial in the regulation of basic cellular processes, including metabolism and gene expression. Glucokinases and hexokinases provide a pool of phosphorylated glucose in an adenosine diphosphate (ADP)- and ATP-dependent manner to shape the cell metabolism. The glucose processing enzymes from Kluyveromyces lactis are poorly characterized despite the emerging contribution of this yeast strain to industrial and laboratory scale biotechnology. The first reports on K. lactis glucokinase (KlGlk1) positioned the enzyme as an essential component required for glucose signaling. Nevertheless, no biochemical and structural information was available until now. Here, we present the first crystal structure of KlGlk1 together with biochemical characterization, including substrate specificity and enzyme kinetics. Additionally, comparative analysis of the presented structure and the prior structures of lactis hexokinase (KlHxk1) demonstrates the potential transitions between open and closed enzyme conformations upon ligand binding.
Highlights
Glucose is one of the main factors in metabolism and key regulators of gene expression in eukaryotic organisms, including yeast, protists, plants, and mammals
Glucose phosphorylating enzymes are crucial in the regulation of basic cellular processes, including metabolism and gene expression
Glucokinases and hexokinases provide a pool of phosphorylated glucose in an adenosine diphosphate (ADP)- and ATP-dependent manner to shape the cell metabolism
Summary
Glucose is one of the main factors in metabolism and key regulators of gene expression in eukaryotic organisms, including yeast, protists, plants, and mammals. Glucose-dependent regulation requires glucose phosphorylation provided by glucose-phosphorylating enzymes, glucokinases, and hexokinases. These enzymes are responsible for intracellular trapping and metabolism initiation of monosaccharides and catalyze ATP-driven phosphorylation, yielding ADP and glucose-6-phosphate. Plant and mammalian cells’ sugar kinases were shown to be responsible for glucose sensing and signaling [7,8,9,10], positioning those enzymes as providers of a carbon source and regulators of sugar-dependent cellular mechanisms. KlHxk hexokinase is the only structurally characterized sugar metabolizing enzyme from K. lactis [22,23,24]. Comparative analysis of the structure of KlGlk reported in this study and the prior structure of KlHxk demonstrates the transitions between open and closed enzyme conformations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
