Bacillus expression vector

Bacillus subtilis Many proteins can be exported into growth medium Easy to grow in large-scale volumes Regulation of gene expression not very well known Lack of high level expression vectors Unable to carry out most post-translational modifications, e.g. glycosylation... 

One way of alleviating a number of these problems is actually to make several parallel clone banks using different expression vectors and strains, regulatable expression systems, and low copy-number vectors. Vectors choices [28] such as plasmids vs phagemids, high vs low copy number vectors, all can affect what is cloned, and there is not one solution which will satisfy every project. Furthermore, the cloning host also makes a difference. E. coli is usually the host of choice, but Bacillus can be preferred for secretable enzymes, and yeast for eukaryotic or post-transitionally modified enzymes. 

Wu, S.C. and Wong, S.L. (1999) Development of improved pUB 110-based vectors for expression and secretion studies in Bacillus subtilis. Journal of Biotechnology, 72 (1-2), 185-195. 

The host bacteria used for production of recombinant proteins are usually E. coli, or Bacillus subtilis they may express proteins at 1 % to over 50% of the cellular protein, depending on such variables as the source, promoter structure, and vector type. Generally the proteins are expressed intracellularly, but leader sequences for excretion may be included. In the latter case, the protein is generally excreted into the periplasmic space, which limits the amount that can be produced. Excretion from grampositive species such as B. subtilis sends the product into the culture medium, with little feedback limitation on total expression level. 

E, and Jaeger, K.E. (2012) Novel broad host range shuttle vectors for expression in Escherichia coli. Bacillus subtilis and Pseudomonas putida. J. Biotechnol, 161 (2), 71-79,... 

Thermostable Neutral Protease Gene from Bacillus stearothermophllus in a Vector Plasmid and Its Expression in Bacillus stearothermophllus and Bacillus subtills, J. Bacterlol.,154 831 (1983). 

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