@article{mbs:/content/journal/jgv/10.1099/0022-1317-72-6-1383, author = "Lankinen, Hilkka and McLauchlan, John and Weir, Malcolm and Furlong, Judy and Conner, Joe and McGarrity, Anne and Mistry, Anil and Clements, J. Barklie and Marsden, Howard S.", title = "Purification and characterization of the herpes simplex virus type 1 ribonucleotide reductase small subunit following expression in Escherichia coli", journal= "Journal of General Virology", year = "1991", volume = "72", number = "6", pages = "1383-1392", doi = "https://doi.org/10.1099/0022-1317-72-6-1383", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-72-6-1383", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", abstract = "The herpes simplex virus type 1 (HSV-1) gene encoding the ribonucleotide reductase (RR) small subunit (R2) was cloned as an unfused and intact open reading frame into a T7 RNA polymerase expression system in Escherichia coli. The expressed product was recovered from bacteria in soluble form and constituted 7% of the soluble protein. Protein purification yielded 3.5 mg of 95% pure R2 per litre of bacterial culture. The correct composition of the purified protein was verified by amino acid analysis and N-terminal sequencing. The isoelectric point of the protein was 5.3. Atomic emission spectroscopy indicated that the iron content of the E. coli-expressed R2 was 0.2 to 0.5 atoms of iron per R2 protomer as compared with a theoretical maximum value of 2. The E. coli-expressed HSV-1 R2 existed as a combination of a stable dimer and monomer. Combination of the E. coli-expressed R2 with the E. coli-expressed large subunit (R1) gave an active holoenzyme. Thus, the T7 expression system provides a rich source of enzymically active HSV-1 RR.", }