D. Das et Mm. Georgiadis, A directed approach to improving the solubility of Moloney murine leukemiavirus reverse transcriptase, PROTEIN SCI, 10(10), 2001, pp. 1936-1941
One of the difficulties that can impede structural work on a molecule of in
terest is limited solubility. Although functionally similar to the human im
munodeficiency virus type-1 reverse transcriptase (HIV-1 RT), the Moloney m
urine leukemia virus reverse transcriptase (MMLV RT) differs both in archit
ecture and solubility properties. Reverse transcriptase is an essential ret
roviral enzyme that replicates the single-stranded RNA genome of the retrov
irus producing a double-stranded DNA copy, which is subsequently integrated
into the host's genome. We have introduced a single amino acid substitutio
n in the connection domain of an N-terminally truncated MMLV RT (L435K) tha
t significantly improves the solubility of the enzyme eliminating the need
for nonionic detergents in buffering storage solutions. The substituted enz
yme retains near wild-type polymerase activity. An important consequence of
the improved solubility of the L435K MMLV RT has been the ability to obtai
n diffraction quality crystals.