The object of the invention is to provide proteins that have both DNA primase activity and DNA polymerase activity. This subject is solved by a protein (p41) that has an amino acid sequence shown in SEQ ID NO: 1. This is for the first time that proteins that have both DNA primase activity and DNA polymerase activity were found. A protein (p46) that has amino acid sequence shown in SEQ ID NO: 2 forms a complex with p41, and enforces DNA synthesis activity that is independent and/or dependent from primer of p41.