Cloning and expression of a soluble sialidase from Chinese hamster ovary cells: sequence alignment similarities to bacterial sialidases

'To whom correspondence should be addressed A cDNA encoding a soluble sialidase from Chinese hamster ovary (CHO) cells has been cloned and expressed. Com-pletely degenerate oligonucleotide primers, which were based on the amino acid sequence of peptides obtained from the purified sialidase (Warner et al., Glycobiology, 3, 455-463, 1993), and the polymerase chain reaction, with single-stranded cDNA template, were employed to generate a unique oligonucleotide probe. The unique probe of 93 bp was used for screening a \gt 10 CHO cell cDNA library. A single clone, which contained a 1.4 kb insert, was isolated after screening 450 000 recombinants. The complete coding region of the protein, 1137 nucleotides, was contained in the isolated clone and it predicted a protein of 379 amino acids. The insert had a 186 bp 5 ' non-coding leader sequence an