一種真菌腈水解酶Nit及其基因序列，該真菌腈水解酶Nit基因全長963個核苷酸，編碼320個氨基酸；以pET-28a(+)為表達質粒，以大腸桿菌Rosetta-gami(DE3)為表達宿主，實現了真菌腈水解酶基因的高效表達，重組菌株大腸桿菌Rosetta-gami(DE3)/pET28a(+)-Nit具有腈水解酶活性，能有效地將底物3-氰基吡啶轉化為煙酸。該真菌腈水解酶的最適反應溫度為45℃，最適反應pH為7.8，重組酶發酵周期短，催化效率高，適合于工業生產煙酸的需要。

1.一種編碼真菌腈水解酶Nit的基因，其特征為核苷酸序列如下所示：1?????ATGTCCAAGA?CTCTCAAAGT?CGCTGCCATC?CAAGCCGAAC?CCGTCTGGAA?CGATCTCCAG61?????GGCGGTGTCA?ACAAGTCCAT?CGGTCTCATC?CAAGAGGCAG?CAAAGAACGG?TGCCAACGTA121??ATCGGCTTCC?CTGAAGTCTT?CATTCCTGGA?TATCCATGGA?GCATCTGGGC?CAACTCGCCT181????ACCGAGAACG?CACCATGGGT?CAATGAGTAC?TTCAAGAACT?CATTGGAGAG?AGAGTCACCT241????GAGATGGACC?AGATCCGAGC?TGCTGTTCGA?GAGGCAGGCG?TCTTTGTAGT?CCTTGGATAT301????AGTGAGAGAT?ACAGGGGAAC?TCTTTACATC?GCACAGTCCT?TCATCGATGA?GACCGGCACT361????ATTGTTCTCC?ACCGCCGCAA?GATCAAGCCC?ACCCATGTTG?AGCGTGCTAT?CTACGGTGAC421????GGACAGGGCG?AGTCTCTGAC?CAATGTCGCC?GACACGAAAT?TTGGCAGGGT?TGCTGGTCTT481????AACTGCTGGG?AGCACACCCA?GACACTTCTC?CGCTACTATG?AATACTCCCA?GGATGTCGAT541????ATCCACGTCT?CCAGCTGGCC?TTCCATCTTC?CCCCAGAACG?TCCCTGAGTG?GCCATACCAT601????ATCACTCCCG?AATGCTGCAA?GGCCTTTTCT?CACGTCGTCT?CCATGGAGGG?AGCCTGCTTC661????GTTCTTCTGG?CAAGTCAGAT?CATGACTGAG?GAGAACCATA?AGAAGGCGAA?CGTTGAAGGC721????TACGACTATA?CTAAGAAGTC?TGGTGGCGGC?TTCAGTATGA?TCTTCTCGCC?TTTCGGAGAG781????GAGCTTGTCA?AGCCCCTTGC?TCCTAACGAG?GAGGGTATTC?TTTACGCTGA?TATCAACCTT841???GAGGAGAAGT?ACAAGGCGAA?GCAGAACTTG?GACATTGTCG?GCCACTACTC?GCGACCCGAC901????CAGCTGAGCC?TTCGCGTCAA?CAAACATGCT?GCCAAGCCTG?TCTTCTTTGC?CAACGACCTG961????TGA。2.一種真菌腈水解酶Nit，其氨基酸序列如下所示：1?????????METSerLysThrLeuLysValAlaAlaIleGlnAlaGluProValTrpAsnAspLeuGln21????????GlyGlyValAsnLysSerIleGlyLeuIleGlnGluAlaAlaLysAsnGlyAlaAsnVal41????????IleGlyPheProGluValPheIleProGlyTyrProTrpSerIleTrpAlaAsnSerPro61????????ThrGluAsnAlaProTrpValAsnGluTyrPheLysAsnSerLeuGluArgGluSerPro81????????GluMETAspGlnIleArgAlaAlaValArgGluAlaGlyValPheValValLeuGlyTyr101???????SerGluArgTyrArgGlyThrLeuTyrIleAlaGlnSerPheIleAspGluThrGlyThr121???????IleValLeuHisArgArgLysIleLysProThrHisValGluArgAlaIleTyrGlyAsp141???????GlyGlnGlyGluSerLeuThrAsnValAlaAspThrLysPheGlyArgValAlaGlyLeu161???????AsnCysTrpGluHisThrGlnThrLeuLeuArgTyrTyrGluTyrSerGlnAspValAsp181???????IleHisValSerSerTrpProSerIlePheProGlnAsnValProGluTrpProTyrHis201???????IleThrProGluCysCysLysAlaPheSerHisValValSerMETGluGlyAlaCysPhe221???????ValLeuLeuAlaSerGlnIleMETThrGluGluAsnHisLysLysAlaAsnValGluGly241???????TyrAspTyrThrLysLysSerGlyGlyGlyPheSerMETIlePheSerProPheGlyGlu261???????GluLeuValLysProLeuAlaProAsnGluGluGlyIleLeuTyrAlaAspIleAsnLeu281???????GluGluLysTyrLysAlaLysGlnAsnLeuAspIleValGlyHisTyrSerArgProAsp301???????GlnLeuSerLeuArgValAsnLysHisAlaAlaLysProValPhePheAlaAsnAspLeu。3.一種用于編碼真菌腈水解酶Nit的表達質粒，其特征在于：含有權利要求1的核苷酸序列，載體為pET28a(+)。4.一種用于生產真菌腈水解酶Nit的重組菌株，其特征在于：將權利要求3中的質粒轉入大腸桿菌E.?coli?Rosetta-gami(DE3)中。5.一種生產真菌腈水解酶并用于轉化生產煙酸的方法，其特征在于：將權利要求4所述的重組菌經發酵培養、產酶誘導，編碼真菌腈水解酶Nit的基因得以表達并在細胞內產生真菌腈水解酶Nit；以3-氰基吡啶為底物時，真菌腈水解酶Nit的最適反應溫度為45?℃，最適反應pH為7.8。