Molecular characterization of TRP1 , a gene coding for trytophan synthetase in the basidiomycete Coprinus cinereus

We utilized a cloned gene (TRP5 ) encoding tryptophan synthetase (TSase) from Saccharomyces cerevisiae to identify and clone the corresponding gene (TRP1 ) from the basidiomycete Coprinus cinereus . The primary nucleotide (nt) sequence of this gene was determined and compared to sequences from other filamentous fungi, as well as to other genes coding for TSase. A transformation assay was used to demonstrate that 321 nt, which do not include CAAT or TATAAA elements and precede the translation initiation codon, are sufficient for expression in a variety of chromosomal locations. The predicted translation product contains 702 amino acids (aa) and is very similar to other TSases, except in the region of aa 257-296 that connects the alpha and beta functional domains.