A novel alcohol dehydrogenase ( CADH ) from Candida albicans was discovered by genome data mining for ketoreductases. CADH was cloned and expressed in Escherichia coli Rosetta( DE3) . Free enzymes usually have poor stability and are difficult to recover and reuse. To overcome such drawbacks, CADH was immobilized as cross⁃linked enzyme aggregates ( CLEAs⁃CA) and the optimum conditions of the immobilization process were investigated. The recombinant product ( CADH ) exhibited specific activity of 1�8 U/mg toward ethyl 4⁃chloro⁃3⁃oxobutanoate ( COBE) ,and the enantiomeric excess purity of (R)⁃CHBE was over 99%. Ammonium sulfate (60%) and 10 mmol/L glutaraldehyde were chosen as the optimum precipitant and cross⁃linker for the preparation of CLEAs. Moreover,addition of substrates ( 50 mmol/L isopropanol and 0�1 mmol/L NAD+) in the immobilization process enhanced the activity recovery by 48�3% as compared to the CLEAs prepared without substrates. CLEAs⁃CA could be reused and still remained about 50% of its initial activity after 19 cycles.%基于基因组序列数据库挖掘新酶的技术，从白色念珠菌Candida albicans基因组中克隆了一条新型醇脱氢酶（ CADH）基因，并在大肠杆菌Escherichia coli Rosetta（ DE3）中表达。为克服游离酶稳定性差、不能重复使用的缺点，探索并优化了交联醇脱氢酶聚集体（ CLEAs CA）的制备条件。结果表明：重组CADH对底物四氯乙酰乙酸乙酯（COBE）的比活力为1�8 U／mg，产物（R）4氯3羟基丁酸乙酯（（R） CHBE）的对映体过量值大于99％。CLEAs CA沉淀剂选择为60％饱和度的（ NH4）2 SO4，交联剂为10 mmol／L 戊二醛。在固定化操作前，加入50 mmol／L异丙醇和0�1 mmol／L NAD＋对CADH催化活性位点、辅酶结合位点进行保护，CLEAs CA的活力回收率提高了48�3％。将CLEAs CA 用于不对称合成（R） CHBE，经过19次的重复使用，CLEAs CA 的活性仍保留有50％。
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