Effects of mutations on herpes simplex virus 1 thymidine kinase functionality: An in vitro assay based on detection of monophosphate forms of acyclovir and thymidine using HPLC/DAD

Discrimination between the mutations responsible for drug resistance and those of UL23 TK gene polymorphism can be difficult. A non-isotopic method has been developed to assess TK functionality by measuring monophosphate forms of both acyclovir (ACV) and thymidine using HPLC/DAD. Phenotypes of TKs could thus be characterized as TK altered (P84L, A189V, L227F), TK deficient (G200S, L291P) or TK partial (R163H). A reliable link between HSV UL23 TK mutations and ACV resistance is necessary for developing a powerful genotyping tool to detect ACV resistance quickly in clinical samples.

► A non-isotopic method to assess TK activity using ACV and dT as substrates.
► Dosage of monophosphate forms of both ACV and dT using HPLC/DAD.
► Phenotypes of TKs characterized as TK altered, TK deficient or TK partial.
► Database of UL23 TK gene completed with six novel mutations.
► Importance for fast and efficient HSV genotyping.