pMAL?系統(tǒng)是一種高效的蛋白融合表達(dá)及純化系統(tǒng)。pMAL載體含有編碼麥芽糖結(jié)合蛋白（Maltose Binding Protein, MBP）的大腸桿菌malE基因，其下游的多克隆位點(diǎn)便于目的基因插入，表達(dá)N端帶有MBP的融合蛋白。通過"tac"強(qiáng)啟動(dòng)子和malE翻譯起始信號(hào)使克隆基因獲得高效表達(dá)，并進(jìn)一步利用MBP對(duì)麥芽糖的親和性達(dá)到用Amylose柱對(duì)融合蛋白的一步親和純化。

The system uses the pMAL vectors which are designed so that insertion interrupts a lacZα gene allowing a blue-to-white screen for inserts on X-gal (5). pMAL-c2 series has an exact deletion of the malE signal sequence, resulting in cytoplasmic expression of the fusion protein. pMAL-p2 series contains the normal malE signal sequence, which directs the fusion protein through the cytoplasmic membrane. pMAL-p2 fusion proteins capable of being exported can be purified from the periplasm. Between the malE sequence and the polylinker there is a spacer sequence coding for 10 asparagine residues. This spacer insulates MBP from the protein of interest, increasing the chances that a particular fusion will bind tightly to the amylose resin. The vectors also include a sequence coding for the recognition site of a specific protease. This allows the protein of interest to be cleaved from MBP after purification, without adding any vector-derived residues to the protein (6). For this purpose, the polylinker includes a restriction site superimposed on the sequence coding for the site of the specific protease. This is where the gene of interest is inserted. An EcoR I site in the same reading frame as that of λgt11 and a number of other useful sites are present directly downstream. The vectors also include the M13 origin of DNA replication which allows the production of single-stranded DNA for sequencing and mutagenesis by infecting with M13KO7 helper phage (NEB #N0315S).

0001 CCGACACCAT CGAATGGTGC AAAACCTTTC GCGGTATGGC ATGATAGCGC CCGGAAGAGA 
0061 GTCAATTCAG GGTGGTGAAT GTGAAACCAG TAACGTTATA CGATGTCGCA GAGTATGCCG 
0121 GTGTCTCTTA TCAGACCGTT TCCCGCGTGG TGAACCAGGC CAGCCACGTT TCTGCGAAAA 
0181 CGCGGGAAAA AGTGGAAGCG GCGATGGCGG AGCTGAATTA CATTCCCAAC CGCGTGGCAC 
0241 AACAACTGGC GGGCAAACAG TCGTTGCTGA TTGGCGTTGC CACCTCCAGT CTGGCCCTGC 
0301 ACGCGCCGTC GCAAATTGTC GCGGCGATTA AATCTCGCGC CGATCAACTG GGTGCCAGCG 
0361 TGGTGGTGTC GATGGTAGAA CGAAGCGGCG TCGAAGCCTG TAAAGCGGCG GTGCACAATC 
0421 TTCTCGCGCA ACGCGTCAGT GGGCTGATCA TTAACTATCC GCTGGATGAC CAGGATGCCA 
0481 TTGCTGTGGA AGCTGCCTGC ACTAATGTTC CGGCGTTATT TCTTGATGTC TCTGACCAGA 
0541 CACCCATCAA CAGTATTATT TTCTCCCATG AAGACGGTAC GCGACTGGGC GTGGAGCATC 
0601 TGGTCGCATT GGGTCACCAG CAAATCGCGC TGTTAGCGGG CCCATTAAGT TCTGTCTCGG 
0661 CGCGTCTGCG TCTGGCTGGC TGGCATAAAT ATCTCACTCG CAATCAAATT CAGCCGATAG 
0721 CGGAACGGGA AGGCGACTGG AGTGCCATGT CCGGTTTTCA ACAAACCATG CAAATGCTGA 
0781 ATGAGGGCAT CGTTCCCACT GCGATGCTGG TTGCCAACGA TCAGATGGCG CTGGGCGCAA 
0841 TGCGCGCCAT TACCGAGTCC GGGCTGCGCG TTGGTGCGGA TATCTCGGTA GTGGGATACG 
0901 ACGATACCGA AGACAGCTCA TGTTATATCC CGCCGTTAAC CACCATCAAA CAGGATTTTC 
0961 GCCTGCTGGG GCAAACCAGC GTGGACCGCT TGCTGCAACT CTCTCAGGGC CAGGCGGTGA 
1021 AGGGCAATCA GCTGTTGCCC GTCTCACTGG TGAAAAGAAA AACCACCCTG GCGCCCAATA 
1081 CGCAAACCGC CTCTCCCCGC GCGTTGGCCG ATTCATTAAT GCAGCTGGCA CGACAGGTTT 
1141 CCCGACTGGA AAGCGGGCAG TGAGCGCAAC GCAATTAATG TAAGTTAGCT CACTCATTAG 
1201 GCACAATTCT CATGTTTGAC AGCTTATCAT CGACTGCACG GTGCACCAAT GCTTCTGGCG 
1261 TCAGGCAGCC ATCGGAAGCT GTGGTATGGC TGTGCAGGTC GTAAATCACT GCATAATTCG 
1321 TGTCGCTCAA GGCGCACTCC CGTTCTGGAT AATGTTTTTT GCGCCGACAT CATAACGGTT 
1381 CTGGCAAATA TTCTGAAATG AGCTGTTGAC AATTAATCAT CGGCTCGTAT AATGTGTGGA 
1441 ATTGTGAGCG GATAACAATT TCACACAGGA AACAGCCAGT CCGTTTAGGT GTTTTCACGA 
1501 GCACTTCACC AACAAGGACC ATAGCATATG AAAATAAAAA CAGGTGCACG CATCCTCGCA 
1561 TTATCCGCAT TAACGACGAT GATGTTTTCC GCCTCGGCTC TCGCCAAAAT CGAAGAAGGT 
1621 AAACTGGTAA TCTGGATTAA CGGCGATAAA GGCTATAACG GTCTCGCTGA AGTCGGTAAG 
1681 AAATTCGAGA AAGATACCGG AATTAAAGTC ACCGTTGAGC ATCCGGATAA ACTGGAAGAG 
1741 AAATTCCCAC AGGTTGCGGC AACTGGCGAT GGCCCTGACA TTATCTTCTG GGCACACGAC 
1801 CGCTTTGGTG GCTACGCTCA ATCTGGCCTG TTGGCTGAAA TCACCCCGGA CAAAGCGTTC 
1861 CAGGACAAGC TGTATCCGTT TACCTGGGAT GCCGTACGTT ACAACGGCAA GCTGATTGCT 
1921 TACCCGATCG CTGTTGAAGC GTTATCGCTG ATTTATAACA AAGATCTGCT GCCGAACCCG 
1981 CCAAAAACCT GGGAAGAGAT CCCGGCGCTG GATAAAGAAC TGAAAGCGAA AGGTAAGAGC 
2041 GCGCTGATGT TCAACCTGCA AGAACCGTAC TTCACCTGGC CGCTGATTGC TGCTGACGGG 
2101 GGTTATGCGT TCAAGTATGA AAACGGCAAG TACGACATTA AAGACGTGGG CGTGGATAAC 
2161 GCTGGCGCGA AAGCGGGTCT GACCTTCCTG GTTGACCTGA TTAAAAACAA ACACATGAAT 
2221 GCAGACACCG ATTACTCCAT CGCAGAAGCT GCCTTTAATA AAGGCGAAAC AGCGATGACC 
2281 ATCAACGGCC CGTGGGCATG GTCCAACATC GACACCAGCA AAGTGAATTA TGGTGTAACG 
2341 GTACTGCCGA CCTTCAAGGG TCAACCATCC AAACCGTTCG TTGGCGTGCT GAGCGCAGGT 
2401 ATTAACGCCG CCAGTCCGAA CAAAGAGCTG GCAAAAGAGT TCCTCGAAAA CTATCTGCTG 
2461 ACTGATGAAG GTCTGGAAGC GGTTAATAAA GACAAACCGC TGGGTGCCGT AGCGCTGAAG 
2521 TCTTACGAGG AAGAGTTGGC GAAAGATCCA CGTATTGCCG CCACTATGGA AAACGCCCAG 
2581 AAAGGTGAAA TCATGCCGAA CATCCCGCAG ATGTCCGCTT TCTGGTATGC CGTGCGTACT 
2641 GCGGTGATCA ACGCCGCCAG CGGTCGTCAG ACTGTCGATG AAGCCCTGAA AGACGCGCAG 
2701 ACTAATTCGA GCTCGAACAA CAACAACAAT AACAATAACA ACAACCTCGG GATCGAGGGA 
2761 AGGATTTCAG AATTCGGATC CTCTAGAGTC GACCTGCAGG CAAGCTTGGC ACTGGCCGTC 
2821 GTTTTACAAC GTCGTGACTG GGAAAACCCT GGCGTTACCC AACTTAATCG CCTTGCAGCA 
2881 CATCCCCCTT TCGCCAGCTG GCGTAATAGC GAAGAGGCCC GCACCGATCG CCCTTCCCAA 
2941 CAGTTGCGCA GCCTGAATGG CGAATGGCAG CTTGGCTGTT TTGGCGGATG AGATAAGATT 
3001 TTCAGCCTGA TACAGATTAA ATCAGAACGC AGAAGCGGTC TGATAAAACA GAATTTGCCT 
3061 GGCGGCAGTA GCGCGGTGGT CCCACCTGAC CCCATGCCGA ACTCAGAAGT GAAACGCCGT 
3121 AGCGCCGATG GTAGTGTGGG GTCTCCCCAT GCGAGAGTAG GGAACTGCCA GGCATCAAAT 
3181 AAAACGAAAG GCTCAGTCGA AAGACTGGGC CTTTCGTTTT ATCTGTTGTT TGTCGGTGAA 
3241 CGCTCTCCTG AGTAGGACAA ATCCGCCGGG AGCGGATTTG AACGTTGCGA AGCAACGGCC 
3301 CGGAGGGTGG CGGGCAGGAC GCCCGCCATA AACTGCCAGG CATCAAATTA AGCAGAAGGC 
3361 CATCCTGACG GATGGCCTTT TTGCGTTTCT ACAAACTCTT TTTGTTTATT TTTCTAAATA 
3421 CATTCAAATA TGTATCCGCT CATGAGACAA TAACCCTGAT AAATGCTTCA ATAATATTGA 
3481 AAAAGGAAGA GTATGAGTAT TCAACATTTC CGTGTCGCCC TTATTCCCTT TTTTGCGGCA 
3541 TTTTGCCTTC CTGTTTTTGC TCACCCAGAA ACGCTGGTGA AAGTAAAAGA TGCTGAAGAT 
3601 CAGTTGGGTG CACGAGTGGG TTACATCGAA CTGGATCTCA ACAGCGGTAA GATCCTTGAG 
3661 AGTTTTCGCC CCGAAGAACG TTCTCCAATG ATGAGCACTT TTAAAGTTCT GCTATGTGGC 
3721 GCGGTATTAT CCCGTGTTGA CGCCGGGCAA GAGCAACTCG GTCGCCGCAT ACACTATTCT 
3781 CAGAATGACT TGGTTGAGTA CTCACCAGTC ACAGAAAAGC ATCTTACGGA TGGCATGACA 
3841 GTAAGAGAAT TATGCAGTGC TGCCATAACC ATGAGTGATA ACACTGCGGC CAACTTACTT 
3901 CTGACAACGA TCGGAGGACC GAAGGAGCTA ACCGCTTTTT TGCACAACAT GGGGGATCAT 
3961 GTAACTCGCC TTGATCGTTG GGAACCGGAG CTGAATGAAG CCATACCAAA CGACGAGCGT 
4021 GACACCACGA TGCCTGTAGC AATGGCAACA ACGTTGCGCA AACTATTAAC TGGCGAACTA 
4081 CTTACTCTAG CTTCCCGGCA ACAATTAATA GACTGGATGG AGGCGGATAA AGTTGCAGGA 
4141 CCACTTCTGC GCTCGGCCCT TCCGGCTGGC TGGTTTATTG CTGATAAATC TGGAGCCGGT 
4201 GAGCGTGGGT CTCGCGGTAT CATTGCAGCA CTGGGGCCAG ATGGTAAGCC CTCCCGTATC 
4261 GTAGTTATCT ACACGACGGG GAGTCAGGCA ACTATGGATG AACGAAATAG ACAGATCGCT 
4321 GAGATAGGTG CCTCACTGAT TAAGCATTGG TAACTGTCAG ACCAAGTTTA CTCATATATA 
4381 CTTTAGATTG ATTTACCCCG GTTGATAATC AGAAAAGCCC CAAAAACAGG AAGATTGTAT 
4441 AAGCAAATAT TTAAATTGTA AACGTTAATA TTTTGTTAAA ATTCGCGTTA AATTTTTGTT 
4501 AAATCAGCTC ATTTTTTAAC CAATAGGCCG AAATCGGCAA AATCCCTTAT AAATCAAAAG 
4561 AATAGACCGA GATAGGGTTG AGTGTTGTTC CAGTTTGGAA CAAGAGTCCA CTATTAAAGA 
4621 ACGTGGACTC CAACGTCAAA GGGCGAAAAA CCGTCTATCA GGGCGATGGC CCACTACGTG 
4681 AACCATCACC CAAATCAAGT TTTTTGGGGT CGAGGTGCCG TAAAGCACTA AATCGGAACC 
4741 CTAAAGGGAG CCCCCGATTT AGAGCTTGAC GGGGAAAGCC GGCGAACGTG GCGAGAAAGG 
4801 AAGGGAAGAA AGCGAAAGGA GCGGGCGCTA GGGCGCTGGC AAGTGTAGCG GTCACGCTGC 
4861 GCGTAACCAC CACACCCGCC GCGCTTAATG CGCCGCTACA GGGCGCGTAA AAGGATCTAG 
4921 GTGAAGATCC TTTTTGATAA TCTCATGACC AAAATCCCTT AACGTGAGTT TTCGTTCCAC 
4981 TGAGCGTCAG ACCCCGTAGA AAAGATCAAA GGATCTTCTT GAGATCCTTT TTTTCTGCGC 
5041 GTAATCTGCT GCTTGCAAAC AAAAAAACCA CCGCTACCAG CGGTGGTTTG TTTGCCGGAT 
5101 CAAGAGCTAC CAACTCTTTT TCCGAAGGTA ACTGGCTTCA GCAGAGCGCA GATACCAAAT 
5161 ACTGTCCTTC TAGTGTAGCC GTAGTTAGGC CACCACTTCA AGAACTCTGT AGCACCGCCT 
5221 ACATACCTCG CTCTGCTAAT CCTGTTACCA GTGGCTGCTG CCAGTGGCGA TAAGTCGTGT 
5281 CTTACCGGGT TGGACTCAAG ACGATAGTTA CCGGATAAGG CGCAGCGGTC GGGCTGAACG 
5341 GGGGGTTCGT GCACACAGCC CAGCTTGGAG CGAACGACCT ACACCGAACT GAGATACCTA 
5401 CAGCGTGAGC TATGAGAAAG CGCCACGCTT CCCGAAGGGA GAAAGGCGGA CAGGTATCCG 
5461 GTAAGCGGCA GGGTCGGAAC AGGAGAGCGC ACGAGGGAGC TTCCAGGGGG AAACGCCTGG 
5521 TATCTTTATA GTCCTGTCGG GTTTCGCCAC CTCTGACTTG AGCGTCGATT TTTGTGATGC 
5581 TCGTCAGGGG GGCGGAGCCT ATGGAAAAAC GCCAGCAACG CGGCCTTTTT ACGGTTCCTG 
5641 GCCTTTTGCT GGCCTTTTGC TCACATGTTC TTTCCTGCGT TATCCCCTGA TTCTGTGGAT 
5701 AACCGTATTA CCGCCTTTGA GTGAGCTGAT ACCGCTCGCC GCAGCCGAAC GACCGAGCGC 
5761 AGCGAGTCAG TGAGCGAGGA AGCGGAAGAG CGCCTGATGC GGTATTTTCT CCTTACGCAT 
5821 CTGTGCGGTA TTTCACACCG CATATATGGT GCACTCTCAG TACAATCTGC TCTGATGCCG 
5881 CATAGTTAAG CCAGTATACA CTCCGCTATC GCTACGTGAC TGGGTCATGG CTGCGCCCCG 
5941 ACACCCGCCA ACACCCGCTG ACGCGCCCTG ACGGGCTTGT CTGCTCCCGG CATCCGCTTA 
6001 CAGACAAGCT GTGACCGTCT CCGGGAGCTG CATGTGTCAG AGGTTTTCAC CGTCATCACC 
6061 GAAACGCGCG AGGCAGCTGC GGTAAAGCTC ATCAGCGTGG TCGTGCAGCG ATTCACAGAT 
6121 GTCTGCCTGT TCATCCGCGT CCAGCTCGTT GAGTTTCTCC AGAAGCGTTA ATGTCTGGCT 
6181 TCTGATAAAG CGGGCCATGT TAAGGGCGGT TTTTTCCTGT TTGGTCACTG ATGCCTCCGT 
6241 GTAAGGGGGA TTTCTGTTCA TGGGGGTAAT GATACCGATG AAACGAGAGA GGATGCTCAC 
6301 GATACGGGTT ACTGATGATG AACATGCCCG GTTACTGGAA CGTTGTGAGG GTAAACAACT 
6361 GGCGGTATGG ATGCGGCGGG ACCAGAGAAA AATCACTCAG GGTCAATGCC AGCGCTTCGT 
6421 TAATACAGAT GTAGGTGTTC CACAGGGTAG CCAGCAGCAT CCTGCGATGC AGATCCGGAA 
6481 CATAATGGTG CAGGGCGCTG ACTTCCGCGT TTCCAGACTT TACGAAACAC GGAAACCGAA 
6541 GACCATTCAT GTTGTTGCTC AGGTCGCAGA CGTTTTGCAG CAGCAGTCGC TTCACGTTCG 
6601 CTCGCGTATC GGTGATTCAT TCTGCTAACC AGTAAGGCAA CCCCGCCAGC CTAGCCGGGT 
6661 CCTCAACGAC AGGAGCACGA TCATGCGCAC CCGTGGCCAG GACCCAACGC TGCCCGAAAT 
6721 T