Distinct mutation in the feline coronavirus spike protein cleavage activation site in a cat with feline infectious peritonitis-associated meningoencephalomyelitis

André, Nicole M; Cossic, Brieuc; Davies, Emma; Miller, Andrew D; Whittaker, Gary R

PCR and sequencing showed the presence of a type I FCoV, based on a sequence alignment with reference genomes. The sequence information obtained from this cat is shown in Figure 2 . The viral sequences from the CNS (brain and spinal cord) contained specific amino acid changes compared with other samples (feces, small intestine, mesenteric lymph node and kidney). The most notable change was an arginine to methionine (R-M) substitution at the critical P1 activation position, 17 corresponding to residue 793. Other changes that correlated with viruses present in the CNS were present in two other positions: 770 alanine to valine (A-V); and 786 threonine to alanine (T-A).