Choline kinase active site provides features for designing versatile inhibitors

Area of Science:

• Biochemistry
• Enzymology
• Drug Discovery

Background:

• Choline kinase (CK) is crucial in cellular metabolism, with human CK alpha (HsCKα) linked to cancer and serving as a drug target.
• Existing inhibitors, like Hemicholinium-3 (HC-3) analogs, primarily target human CK.
• Pathogenic CKs, such as Plasmodium falciparum CK (PfCK), are potential targets for anti-infective therapies.

Purpose of the Study:

• To investigate the conserved nature of the ATP and choline binding sites across different Choline Kinase isoforms.
• To explore the potential of existing human CK inhibitors against pathogenic CKs.
• To provide a basis for designing novel, broad-spectrum CK inhibitors.

Main Methods:

• Molecular dynamic simulations to analyze binding site conservation.
• Experimental assays to determine compound binding affinities to various CK isoforms.
• Biochemical characterization of enzyme-inhibitor interactions.

Main Results:

• Molecular dynamics revealed conserved ATP and choline binding pockets in human and pathogenic CKs.
• Experimental data confirmed that two distinct compounds inhibit human CK alpha 1 (HsCKα1), PfCK, and Candida parapsilosis CK (CpCK) in the low micromolar range.
• These findings demonstrate cross-reactivity of inhibitors between human and pathogenic CKs.

Conclusions:

• The conserved choline binding pocket across different species presents a viable target for novel inhibitor design.
• Compounds inhibiting human CK may be repurposed or adapted for treating infections caused by pathogens expressing CK.
• This study supports the development of dual-acting inhibitors for both cancer and infectious diseases.