TABLE 2.

Growth properties and sequences of A₂₄Cruz viruses recovered from BHK transfected cells

RNA sourcea	Encoded amino acid sequenceb	Transfected cell line	Virus growth, plaque phenotypec	Emergent amino acid sequenced	Additional P1 amino acid changes (expt 1/expt 2)e
A24-RRGD (wt)	RRGDMGS	BHK-21	+++, C	RRGDMGS	None/none
		BHK3αvβ6	+++, C	-------
A24-RSGD (B9-like)	SGDMES	BHK-21	+++, C	-----E-	None/none
		BHK3αvβ6	+++, T	-S---E-
A24-R*SGD	RSGDMES	BHK-21	++, T	-S---A-	None/none
		BHK3αvβ6	+++, T	-S---E-
A24-K*SGD	KSGDMES	BHK-21	++, T	KS---A-	None/VP2 (D85H)
		BHK3αvβ6	+++, T	KS---E-	None/none
A24-*E*SGD	ESGDMES	BHK-21	++, T	ES---A-	None/none
		BHK3αvβ6	+++, T	ES---A-	None/VP3 (E196V), VP4 (N41K)

^aTransfections with transcript RNAs derived from the indicated sources were carried out as described in Materials and Methods. Transfections were repeated twice in each cell line. The * indicates that a double mutation was introduced in the coding sequence of the amino acid just downstream of the symbol relative to the sequence found in the wild-type (RGD) virus. wt, wild type.

^bSequence of amino acids 143 to 149 of VP1.

^cGrowth properties of wild-type and mutant FMDVs. +++, wild-type growth; ++, slower than wild-type growth. Plaque phenotype on BHK-21 cell monolayers stained at 48 hours postinoculation was scored as turbid (T) or clear (C).

^dVirus derived from two independent transfections in BHK-21 or BHK3α_vβ₆ cells was passaged two additional times in the same cell line and the P1 sequences were determined. The wild-type A₂₄Cruz virus 143-149 VP1 sequence encoding the RGD triplet (underlined) is displayed; the dashes represent conserved residues, and the emergent mutations from the original cDNA are indicated in boldface letters.

^eThe result of two transfection experiments is indicated.