[1] He then moved to Lomonosov Moscow State University, where he studied enzyme kinetics and received the Candidate of Sciences degree (equivalent to PhD at that time) in 1983.

[5] The research interests of Šikšnys include structure-function relationships of enzymes involved in nucleic acids metabolism.

Šikšnys and members of his laboratory perform biochemical, biophysical and structural studies of proteins involved in bacterial antiviral defense, including restriction endonucleases and CRISPR-Cas systems.

Since 2007 Šikšnys focused on mechanistic studies of CRISPR-Cas, the newly discovered bacterial antiviral systems, and was among the first to demonstrate programmable DNA cleavage by the Cas9 protein.

[6][7][8][9] According to Šikšnys, his article was not even considered as serious by the editor board of the academic journal and was not sent to the reviewers, therefore the time needed to be recognized as first was lost.