Bacillus megaterium Shuttle Vector

The Bacillus megaterium expression system provides a versatile and easy-to-handle tool for stable and high-yield protein production, both small- and large-scale.

B. megaterium has proven to be an excellent host for the expression of non-homologous DNA. Unlike other bacilli strains, none of the alkaline proteases are present. This enables cloning and expression of foreign proteins without degradation.

In addition, there are no endotoxins found in the cell wall. B. megaterium can stably maintain several extra-chromosomal DNA elements in parallel. Protein yields are exceptionally high, even if inexpensive substrates are used. B. megaterium protoplasts ready for transformation can be ordered separately.

Multiple B. megaterium shuttle vectors are available, as well as several control vectors. The shuttle vectors are divided into two series:

Vectors of the 1520 Series

• pWH1520 (BMEG03) - original shuttle vector of the 1520 series. All BMEG vectors, with the exception of pMGBm19, were derived from pWH1520.

• pMM1522 (BMEG10) - version of pWH1520 with additional restriction site BsrGI upstream of the ATG. The BsrGI site can be used to clone the gene of interest with its native start codon (corresponding to the native N-terminus of the protein of interest). The vector contains a stop codon downstream of the ATG (> 120 bp).

• pMM1525 (BMEG11) - secretion vector; version of pMM1522 with additional signal sequence for protein secretion (SPlipA) upstream of the MCS (the native lipA encodes for an extracellular esterase).

• pHIS1522 (BMEG12) - version of pMM1522 with additional sequence for C-terminal 6xHis-tag fusion (including stop codon).

• pHIS1525 (BMEG13) - secretion vector; version of pMM1525 with additional sequence for C-terminal 6xHis-tag fusion (including stop codon).

• pSTREP1525 (BMEG14) - secretion vector; version of pMM1525 with additional sequence for N-terminal Strep-tag fusion (cleavable with Factor Xa protease) and stop codon downstream of the MCS; does not contain BsrGI restriction site.

• pSTREPHIS1525 (BMEG15) - secretion vector; version of pMM1525 with additional sequences for N-terminal Strep-tag (cleavable with Factor Xa protease) and C-terminal His-tag fusion (including stop codon); does not contain a BsrGI restriction site.

• pC-His1622 (BMEG20) - size-reduced pHIS1522 variant with sequence for C-terminal 6xHis-tag fusion (including stop codon right downstream of the tag).

• pC-Strep1622 (BMEG21) - size-reduced pHIS1522 variant with sequence for C-terminal StrepII-tag fusion (including stop codon directly downstream of the tag).

Vectors of the 1622 Series

• pC-His1622 (BMEG20) - size-reduced pHIS1522 variant with sequence for C-terminal 6xHis-tag fusion (including stop codon right downstream of the tag).

• pC-Strep1622 (BMEG21) - size-reduced pHIS1522 variant with sequence for C-terminal StrepII-tag fusion (including stop codon directly downstream of the tag).

• pN-His-TEV1622 (BMEG22) - version of pSTOP1622 with an additional sequence for N-terminal 6xHis-tag fusion; cleavable with TEV (tobacco etch virus) protease.

• pN-Strep-TEV1622 (BMEG23) - version of pSTOP1622 with an additional sequence for N-terminal fusion of StrepII-tag; cleavable with TEV (tobacco etch virus) protease. 

• pN-StrepXa1622 (BMEG24) - version of pSTOP1622 with additional sequence for N-terminal fusion of StrepII-tag; cleavable with Factor Xa protease.

• pSTOP1622 (BMEG25) - size-reduced pMM1522 variant with a stop codon directly downstream of the MCS.