3.1.1.53	A385T	naturally occuring mutation	730718	
3.1.1.53	A394T	naturally occuring mutation	730718	
3.1.1.53	A467V	naturally occuring mutation from patients with anti-PIT-1 antibody syndrome. The mutation occurs in a heterozygous state in all the patients with anti-PIT-1 antibody syndrome, and in 6% of control subjects, the prevalence is significantly increased in the patients	729642	
3.1.1.53	A467V	naturally occuring mutation, the enzyme shows over 110% catalytic activity compared to the wild-type enzyme. The mutant is secreted upon overexpression	730718	
3.1.1.53	C196F	naturally occuring mutation, the mutant shows highly reduced catalytic activity compared with the wild-type enzyme	730718	
3.1.1.53	C443R	naturally occuring mutation	730718	
3.1.1.53	E26A	site-directed mutagenesis, the mutant shows highly reduced activity compared to the wild-type NanS	716859	
3.1.1.53	F211A	abrogated ligand recognition and binding	700987	
3.1.1.53	F404S	naturally occuring mutation	730718	
3.1.1.53	G419E	naturally occuring mutation	730718	
3.1.1.53	G514A	naturally occuring mutation	730718	
3.1.1.53	G64S	naturally occuring mutation, the enzyme shows unaltered catalytic activity compared to the wild-type enzyme. The mutant enzyme is poorly secreted when overexpressed	730718	
3.1.1.53	H301N	site-directed mutagenesis, inactive mutant	716859	
3.1.1.53	H377A	complete loss of activity	750708	
3.1.1.53	H377A	the mutation abolishes the enzymatic activity	750708	
3.1.1.53	H447R	naturally occuring mutation	730718	
3.1.1.53	H472Q	naturally occuring mutation	730718	
3.1.1.53	K434T	naturally occuring mutation	730718	
3.1.1.53	K71R	naturally occuring mutation from patients with anti-PIT-1 antibody syndrome. The mutation occurs in a heterozygous state in 2 of 3 patients with anti-PIT-1 antibody syndrome, and in 11% of control subjects, the prevalence is significantly increased in the patients	729642	
3.1.1.53	K71R	naturally occuring mutation, the enzyme shows over 50% catalytic activity compared to the wild-type enzyme. The mutant is secreted upon overexpression	730718	
3.1.1.53	L266A	abrogated ligand recognition and binding	700987	
3.1.1.53	L267A	abrogated ligand recognition and binding	700987	
3.1.1.53	M456I	naturally occuring mutation	730718	
3.1.1.53	M456T	naturally occuring mutation	730718	
3.1.1.53	M89V	naturally occuring mutation, the enzyme shows unaltered catalytic activity compared to the wild-type enzyme. The mutant enzyme is poorly secreted when overexpressed	730718	
3.1.1.53	additional information	construction of recombinant MHV-A59 derivatives in which the autologous genes for hemagglutinin-esterase and sialidase are replaced by those of MHV-S or MHV-DVIM by targeted RNA recombination. The mutants do not express functional hemagglutinin-esterase, in MHV-A59, the hemagglutinin-esterase gene is interrupted by a nonsense mutation at codon 15 and that consequently MHV-A59 and derivates rMHV-A59-SDVIM and rMHV-A59-SS do not express the hemagglutinin-esterase protein	716066	
3.1.1.53	additional information	the mutant SsNeuAs truncated from 166 to 233 amino acids at the N-terminal a re active for pNP-Ac and their esterase activities are almost the same as the wild-type, only with one exception of the SsNeuA167-410, while the mutant SsNeuAs terminated at amino acid position of 227, 232, 233, 241, 247, 267, 283, 293, 312, 322, 338, 355 and 377 are inactive in CMP-Neu5Ac synthetase activity, even removal of 33 amino acid residues at C-terminal of the SsNeuA leads to a complete loss of CMP-Neu5Ac synthetase activity	714062	
3.1.1.53	Q309P	naturally occuring mutation, the mutant shows highly reduced catalytic activity compared with the wild-type enzyme	730718	
3.1.1.53	Q335P	naturally occuring mutation, the mutant shows highly reduced catalytic activity compared with the wild-type enzyme	730718	
3.1.1.53	Q428L	naturally occuring mutation	730718	
3.1.1.53	Q462R	naturally occuring mutation	730718	
3.1.1.53	R387W	naturally occuring mutation	730718	
3.1.1.53	R393C	naturally occuring mutation	730718	
3.1.1.53	R393H	naturally occuring mutation	730718	
3.1.1.53	R479C	naturally occuring mutation	730718	
3.1.1.53	S127A	naturally occuring mutation, the enzyme shows below 10% catalytic activity compared to the wild-type enzyme	730718	
3.1.1.53	S19A	site-directed mutagenesis, inactive mutant	716859	
3.1.1.53	S258A	site-directed mutagenesis	714062	
3.1.1.53	S300A	site-directed mutagenesis, the mutant shows reduced activity compared to the wild-type NanS	716859	
3.1.1.53	S332A	no significant influence on activity	750708	
3.1.1.53	S332A	the mutation does not influence the activity of the enzyme significantly	750708	
3.1.1.53	S40A	catalytically inactive, active site residue, retained lectin activity	700987	
3.1.1.53	S57T	loss of esterase activity	673893	
3.1.1.53	T132A	complete loss of activity	750708	
3.1.1.53	T132A	the mutation abolishes the enzymatic activity	750708	
3.1.1.53	T294A	site-directed mutagenesis, the mutant shows reduced activity compared to the wild-type NanS	716859	
3.1.1.53	T294S	site-directed mutagenesis, the mutant shows reduced activity compared to the wild-type NanS	716859	
3.1.1.53	V459I	naturally occuring mutation	730718	
3.1.1.53	Y184A	decreased ligand binding affinity	700987