Novel shuttle vector

Abstract

The present invention provides a shuttle vector for a microorganism of the genus Bifidobacterium (BM) and Escherichia coli having a wide host range and a large copy number in BM and capable of highly expressing a desired protein when used as an expression vector; an expression vector capable of expressing a desired gene in BM by use of the shuttle vector; BM transformed with the expression vector; and an antitumor agent comprising the BM as an active ingredient. The vector comprises a pTB6-derived region portion comprising a replication origin (oriV)-repB region of pTB6 but not comprising MembB, MobA, OrfI, and oriT regions of pTB6 and an Escherichia coli-derived plasmid portion comprising a replication origin (oriC) region of Escherichia coli but having deleted DNA encoding an N-terminal region of an ampicillin resistance gene (ampR) expression product -lactamase, and constitute a shuttle vector for Escherichia coli with a BM having an average copy number of 6 to 30.

Description

technical field

[0001] The present invention relates to a shuttle vector between microorganisms of the genus Bifidobacterium and Escherichia coli, an expression vector capable of expressing a desired gene in microorganisms of the genus Bifidobacterium using the shuttle vector, and microorganisms of the genus Bifidobacterium transformed with the shuttle vector And an antitumor agent using the microorganism of the genus Bifidobacterium as an active ingredient. Background technique

[0002] Bifidobacterium longum (Bifidobacterium longum) is a Gram-positive anaerobic bacterium whose genome has a high GC content (see, for example, Non-Patent Document 1). Such Bifidobacterium longum is non-pathogenic, and constitutes most of the normal microbiota in the large intestine of humans and other animals (see, for example, Non-Patent Document 2). It is generally believed that it can: improve immune response (for example, refer to Non-Patent Document 3), have an inhibitory effect on the o...

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