RT Journal Article SR Electronic(1) A1 Kadaré, Gress A1 Rozanov, Mikhail A1 Haenni, Anne-LiseYR 1995 T1 Expression of the turnip yellow mosaic virus proteinase in Escherichia coli and determination of the cleavage site within the 206 kDa protein JF Journal of General Virology, VO 76 IS 11 SP 2853 OP 2857 DO https://doi.org/10.1099/0022-1317-76-11-2853 PB Microbiology Society, SN 1465-2099, AB The large non-structural polyprotein (206 kDa) of turnip yellow mosaic tymovirus (TYMV) undergoes auto-cleavage, producing N- and C-terminal proteins. Here we show that the viral proteinase responsible for this event is active when produced in Escherichia coli, as monitored in Western blots by examining the generation of the C-terminal cleavage product after induction by IPTG. The outer boundaries and critical amino acids of the proteinase domain were characterized by deletion analysis and site-directed mutagenesis. A miniproteinase of 273 residues resulting from combined N- and C- terminal deletions still performed efficient cleavage. Sequence analysis of the bacterially-purified C-terminal cleavage product indicated that cleavage occurs between Ala1259 and Thr1260 of the non-structural protein., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-76-11-2853