Abstract: Vectors expressible in a host that is the rhaBAD promoter region of the L-rhamnose operon operably linked to a transcriptional unit that is: a) a nucleic acid sequence which is heterologouse to the host, and b) a prokaryotic signal sequence operably linked to the nucleic acid sequence. The prokaryotic signal sequence is selected from signal peptides of periplasmatic binding proteins for sugars, amino acids, vitamins and ions. The expression of the nucleic acid sequence is controlled by the promoter region. The vector is used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. This is an isolated and purified nucleic acid sequence expressible in a host is the promoter region of the L-rhamnose operon. There is a method for producing a polypeptide in a host using the vector.

Abstract: Vectors expressible in a host that is the rhaBAD promoter region of the L-rhamnose operon operably linked to a transcriptional unit that is: a) a nucleic acid sequence which is heterologous to the host, and b) a prokaryotic signal sequence operably linked to the nucleic acid sequence. The prokaryotic signal sequence is selected from signal peptides of periplasmatic binding proteins for sugars, amino acids, vitamins and ions. The expression of the nucleic acid sequence is controlled by the promoter region. The vector is used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. This is an isolated and purified nucleic acid sequence expressible in a host is the promoter region of the L-rhamnose operon. There is a method for producing a polypeptide in a host using the vector.

Abstract: New vectors expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. The new vector can be used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. There is an isolated and purified nucleic acid sequence expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes a nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. A prokaryotic host is transformed with the vector or the isolated and purified nucleic acid sequence. There is a method for producing a polypeptide in a host using the vector.

Abstract: Vectors expressible in a host that is the rhaBAD promoter region of the L-rhamnose operon operably linked to a transcriptional unit that is: a) a nucleic acid sequence which is heterologous to the host, and b) a prokaryotic signal sequence operably linked to the nucleic acid sequence. The prokaryotic signal sequence is selected from signal peptides of periplasmatic binding proteins for sugars, amino acids, vitamins and ions. The expression of the nucleic acid sequence is controlled by the promoter region. The vector is used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. This is an isolated and purified nucleic acid sequence expressible in a host is the promoter region of the L-rhamnose operon. There is a method for producing a polypeptide in a host using the vector.

Abstract: New vectors expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. The new vector can be used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. There is an isolated and purified nucleic acid sequence expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes a nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. A prokaryotic host is transformed with the vector or the isolated and purified nucleic acid sequence. There is a method for producing a polypeptide in a host using the vector.

Abstract: New vectors expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. The new vector can be used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. There is an isolated and purified nucleic acid sequence expressible in a host comprising the promoter region of the melibiose operon operably linked to a transcriptional unit that includes a nucleic acid sequence which is heterologous to the host. The expression of the nucleic acid sequence is controlled by the promoter region of the melibiose operon. A prokaryotic host is transformed with the vector or the isolated and purified nucleic acid sequence. There is a method for producing a polypeptide in a host using the vector.

Abstract: Vectors expressible in a host that is the rhaBAD promoter region of the L-rhamnose operon operably linked to a transcriptional unit that is: a) a nucleic acid sequence which is heterologouse to the host, and b) a prokaryotic signal sequence operably linked to the nucleic acid sequence. The prokaryotic signal sequence is selected from signal peptides of periplasmatic binding proteins for sugars, amino acids, vitamins and ions. The expression of the nucleic acid sequence is controlled by the promoter region. The vector is used for the regulated heterologous expression of a nucleic acid sequence in a prokaryotic host. This is an isolated and purified nucleic acid sequence expressible in a host is the promoter region of the L-rhamnose operon. There is a method for producing a polypeptide in a host using the vector.

Abstract: In DNA fragments and plasmids comprising the bioB, bioF, bioC, bioD and bioA genes responsible for biosynthesis of biotin, or their functionally equivalent genetic variants and mutants from enteric bacteria, the genes are arranged in a transcription unit. These DNA fragments and plasmids can be contained in microorganisms which can be used to produce biotin.