| A strain of Penicillium sp. GXCR1 was isolated from waste sludge out of the effluent channel in the mining area. The GXCR1 has very high copper resistance, and was susceptible to the Benomyl. The nucleotide sequences of ITS DNA of the GXCR1 shared more than 95% homology with 102 strains of P.spp. Its optimum growth temperature was at 32 , and the optimum growth pH was at pH 5.On the PDA medium, the level of Cu2+resistance of the GXCR1 was 200mM, and even up to 800mM if in the presence of 5mM Mn2+.In the liquid medium PDB with the added individual metal salt, the minimal concentration of the individual heavy metal inhibiting the GXCR1 growth was > 200mM Cu2+, >1200mM Zn2+,>500mM Al34 and 60mM Cr3+, 10mM Cd2+ ,10mM Pb2+ , 10mM Ni2+ and 3mM Cr6+ respectively; It could growth well in liquid medium PDB with one of the following heavy metal combinations: 40mM Cu2+, 200mM Zn2+ and 1mM Cd2+, 40mM Cu2+, 100mM Zn2+and 3mM Pb2+, or 200mM Zn2+, 3mM Cd2+ and 3mM Pb2+.The biosorption capacity of heavy metals of the GXCR1 was up to 26.19mg Cu2+/g DW and 258.3mgZn2+/g DW respectively. The quantity of to Cu2+ and Zn2+ biossorption of the mycelium surfaces was much larger than that of both accumulation inside the cells of mycelia. The biosorption of mycelia pretreated with 0.2M NaOH was up to 76.9mg Cu2+/g DW. The Cu2+ biosorption quantity of mycelia was much larger than that of Zn2+ biosorption when under coexsistance of both metal salts.The optimum mycelial age for preparation of protoplast was at 24h time-point after inoculation and culture of conidia. The rate of the prepared protoplast was 3.2 107/ml. The reproduction rate of the prepared protoplast was up to 31%. Efficiency of protoplast transformation with the plasmid was 0.3 transformants/ug DNA.A strain of the mutant MGXCR1 with a much lower level of Cu resistance was selected by ultraviolet mutagenesis from the wild type strain GXCR1.
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