Abstract：A complete chitin deacetylase (CDA) cDNA from Mucor racemonus was cloned and sequenced by using RT-PCR and RACE with special conserved primers. The cDNA sequence was submitted to GeneBank (DQ538514). The results showed: (1) The complete gene with length of 1506bp contains 67bp 5’-untranslated region, an open reading frame of 1357bp and 82bp 3’-untranslated region including tailing site AATAAA. The gene encodes a sequence of 448 amino acid residues and consists of core nucleotides encoding a polysaccharide deacetylase domain which covering 32 of the entire sequence. (2) The CDA gene shares high sequence similarity with that of fungi including Rhizopus oryzae (75%), CDA1(58%) and CDA2(56%) of Rhizopus circinans, Mucor rouxii(56%), Gongreonella bulteri(48%), Rhizopus stolonifer(39%), Phycomyces blakesleeanus(39%), CDA1(17%) and CDA2(16%) of Saccharomyces cerevisiae. The corresponding homology of the deduced amino acid sequences was 69%, 57%, 59%, 55%, 47%, 30%, 32%, 18% and 21%, respectively. (3) Phylogenetic analysis according to the deduced amino acid sequences was marched with the classical taxonomic classification of the fungi. (4) The 3-D-structure of this protein was predicted. The protein has a whole CDA functional domain and a polysaccharide deacetylase domain.
