pMAL-c4x vector (V006797)

MSDS

Basic Vector Information

The pMAL-4 vectors (Figure 1) provide a method for expressing and purifying a protein produced from a cloned gene or open reading frame. The cloned gene is inserted downstream from the malE gene of E. coli, which encodes maltose-binding protein (MBP), resulting in the expression of an MBP fusion protein (1,2). The MBP in these vectors has been engineered for tighter binding to amylose. The method uses the strong “tac” promoter and the malE translation initiation signals to give high-level expression of the cloned sequences (3,4), and a one-step purification of the fusion protein using MBP’s affinity for maltose (5). The vectors express the malE gene (with or without its signal sequence) fused to the lacZα gene. Restriction sites between malE and lacZα are available for inserting the coding sequence of interest. Insertion inactivates the β-galactosidase α-fragment activity of the malE-lacZα fusion, which results in a blue to white color change on Xgal plates when the construction is transformed into an α-complementing host such as TB1, JM107 or NEB 5-alpha Competent E. coli (6,7). When present, the signal peptide on pre-MBP directs fusion proteins to the periplasm. For fusion proteins that can be successfully exported, this allows folding and disulfide bond formation to take place in the periplasm of E. coli, as well as allowing purification of the protein from the periplasm (8). The vectors carry the lacIq gene, which codes for the Lac repressor. This keeps expression from Ptac low in the absence of IPTG induction. The pMAL-4 vectors also contain the sequence coding for the recognition site of a specific protease, located just 5´ to the polylinker insertion sites. This allows MBP to be cleaved from the protein of interest after purification. The pMAL-c4X and pMAL-p4X vectors that are included in the system encode the site for Factor Xa (9, 10). Factor Xa cleaves after its four amino acid recognition sequence, so that few or no vector-derived residues are attached to the protein of interest, depending on the site used for cloning. pMAL vectors containing sites for alternative proteases are also available (Figure 1). The vectors pMAL-c4G (NEB #N8106) and pMAL-p4G (NEB #N8103) encode the site for GenenaseI (NEB #P8075), which cleaves following the sequence His-Tyr. The vectors pMAL-c4E (NEB #N8105) and pMAL-p4E (NEB #N8102) encode the site for Enterokinase (NEB #P8070), which cleaves following the sequence Asp-Asp-Asp-Asp-Lys.

Vector Name:: pMAL-c4x

Antibiotic Resistance:: Ampicillin

Length:: 6645 bp

Type:: E. coli Expression Vectors

Replication origin:: ori

Copy Number:: High copy number

Promoter:: Tac

Cloning Method:: Enzyme digestion and ligation

5' Primer:: MalE: 5'-GGTCGTCAGACTGTCGATGAAGCC-3'; MBP-F: 5'-gatgaagccctgaaagacgcgcag-3'

3' Primer:: pBad-R: 5'-gatttaatctgtatcagg-3'; M13-F: 5'-TGTAAAACGACGGCCAGT-3'

Fusion Tag:: N-MBP, N-Factor Xa

pMAL-c4x vector Vector Map

View Map in NovoBuilder

Plasmid Resuspension Protocol:

1. Centrifuge at 5,000×g for 5 min.

2. Carefully open the tube and add 20 μl of sterile water to dissolve the DNA.

3. Close the tube and incubate for 10 minutes at room temperature.

4. Briefly vortex the tube and then do a quick spin to concentrate the liquid at the bottom. Speed is less than 5000×g.

5.Store the plasmid at -20 ℃.

pMAL-c4x vector Sequence

Copy Sequence

Download GeneBank File(.gb)

LOCUS       40924_29711        6645 bp DNA     circular SYN 13-JAN-2022
DEFINITION  synthetic circular DNA.
ACCESSION   .
VERSION     .
KEYWORDS    .
SOURCE      synthetic DNA construct
  ORGANISM  synthetic DNA construct
REFERENCE   1  (bases 1 to 6645)
  TITLE     Direct Submission
REFERENCE   2  (bases 1 to 6645)
  AUTHORS   .
  TITLE     Direct Submission
COMMENT     SGRef: number: 1; type: "Journal Article"
FEATURES             Location/Qualifiers
     source          1..6645
                     /mol_type="other DNA"
                     /organism="synthetic DNA construct"
     promoter        3..80
                     /label=lacIq promoter
                     /note="In the lacIq allele, a single base change in the
                     promoter boosts expression of the lacI gene about 10-fold."
     CDS             81..1160
                     /codon_start=1
                     /label=lacI
                     /note="lac repressor"
                     /translation="VKPVTLYDVAEYAGVSYQTVSRVVNQASHVSAKTREKVEAAMAEL
                     NYIPNRVAQQLAGKQSLLIGVATSSLALHAPSQIVAAIKSRADQLGASVVVSMVERSGV
                     EACKAAVHNLLAQRVSGLIINYPLDDQDAIAVEAACTNVPALFLDVSDQTPINSIIFSH
                     EDGTRLGVEHLVALGHQQIALLAGPLSSVSARLRLAGWHKYLTRNQIQPIAEREGDWSA
                     MSGFQQTMQMLNEGIVPTAMLVANDQMALGAMRAITESGLRVGADISVVGYDDTEDSSC
                     YIPPLTTIKQDFRLLGQTSVDRLLQLSQGQAVKGNQLLPVSLVKRKTTLAPNTQTASPR
                     ALADSLMQLARQVSRLESGQ"
     protein_bind    1176..1197
                     /label=CAP binding site
                     /note="CAP binding activates transcription in the presence
                     of cAMP."
     promoter        1406..1434
                     /label=tac promoter
                     /note="strong E. coli promoter; hybrid between the trp and
                     lac UV5 promoters"
     protein_bind    1442..1458
                     /label=lac operator
                     /note="The lac repressor binds to the lac operator to
                     inhibit transcription in E. coli. This inhibition can be 
                     relieved by adding lactose or 
                     isopropyl-beta-D-thiogalactopyranoside (IPTG)."
     CDS             1528..2628
                     /codon_start=1
                     /label=MBP
                     /note="maltose binding protein from E. coli"
                     /translation="MKIEEGKLVIWINGDKGYNGLAEVGKKFEKDTGIKVTVEHPDKLE
                     EKFPQVAATGDGPDIIFWAHDRFGGYAQSGLLAEITPDKAFQDKLYPFTWDAVRYNGKL
                     IAYPIAVEALSLIYNKDLLPNPPKTWEEIPALDKELKAKGKSALMFNLQEPYFTWPLIA
                     ADGGYAFKYENGKYDIKDVGVDNAGAKAGLTFLVDLIKNKHMNADTDYSIAEAAFNKGE
                     TAMTINGPWAWSNIDTSKVNYGVTVLPTFKGQPSKPFVGVLSAGINAASPNKELAKEFL
                     ENYLLTDEGLEAVNKDKPLGAVALKSYEEELVKDPRIAATMENAQKGEIMPNIPQMSAF
                     WYAVRTAVINAASGRQTVDEALKDAQT"
     CDS             2677..2688
                     /codon_start=1
                     /label=Factor Xa site
                     /note="Factor Xa recognition and cleavage site"
                     /translation="IEGR"
     primer_bind     complement(2736..2752)
                     /label=M13 fwd
                     /note="common sequencing primer, one of multiple similar 
                     variants"
     terminator      3101..3187
                     /label=rrnB T1 terminator
                     /note="transcription terminator T1 from the E. coli rrnB
                     gene"
     terminator      3279..3306
                     /label=rrnB T2 terminator
                     /note="transcription terminator T2 from the E. coli rrnB
                     gene"
     promoter        3325..3416
                     /label=AmpR promoter
     CDS             3417..4274
                     /codon_start=1
                     /label=AmpR
                     /note="beta-lactamase"
                     /translation="MSIQHFRVALIPFFAAFCLPVFAHPETLVKVKDAEDQLGARVGYI
                     ELDLNSGKILESFRPEERFPMMSTFKVLLCGAVLSRVDAGQEQLGRRIHYSQNDLVEYS
                     PVTEKHLTDGMTVRELCSAAITMSDNTAANLLLTTIGGPKELTAFLHNMGDHVTRLDRW
                     EPELNEAIPNDERDTTMPVAMATTLRKLLTGELLTLASRQQLIDWMEADKVAGPLLRSA
                     LPAGWFIADKSGAGERGSRGIIAALGPDGKPSRIVVIYTTGSQATMDERNRQIAEIGAS
                     LIKHW"
     rep_origin      complement(4319..4832)
                     /direction=LEFT
                     /label=M13 ori
                     /note="M13 bacteriophage origin of replication; arrow
                     indicates direction of (+) strand synthesis"
     rep_origin      4943..5531
                     /label=ori
                     /note="high-copy-number ColE1/pMB1/pBR322/pUC origin of 
                     replication"
     misc_feature    complement(5717..5859)
                     /label=bom
                     /note="basis of mobility region from pBR322"
     CDS             complement(5964..6152)
                     /codon_start=1
                     /label=rop
                     /note="Rop protein, which maintains plasmids at low copy
                     number"
                     /translation="VTKQEKTALNMARFIRSQTLTLLEKLNELDADEQADICESLHDHA
                     DELYRSCLARFGDDGENL"

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