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H Heyneker

Publications and source records attributed to H Heyneker.

5 recordsLinked to original sources

High-level secretion of human growth hormone by Escherichia coli.

A gene encoding the mature form of human growth hormone (hGH) was fused to the secretion signal coding sequence of the Escherichia coli heat-stable enterotoxin II (STII). This hybrid gene was preceded by two Shine-Dalgarno sequences derived from the trp and STII-coding genes and was expressed in E. coli under the transcriptional control of the E. coli alkaline phosphatase (phoA) promoter. In low-phosphate growth media, cells synthesized about 15 to 25 micrograms of hGH/ml/1 A550 unit of cells. This represents 6 to 10% of total cellular protein. The majority of the hGH produced (more than 90%) was processed precisely and secreted into the periplasmic space. These results demonstrate that E. coli cells are able to synthesize and secrete high levels of this human protein using a prokaryotic signal sequence.

Chorionic Gonadotropin↗

Complete nucleotide sequence of the glutamate dehydrogenase gene from Escherichia coli K-12.

A 2.3-kb PstI- ClaI chromosomal DNA segment, carrying the complete coding region of the glutamate dehydrogenase (GDH) structural gene from Escherichia coli K-12, has been sequenced. The complete amino acid sequence (447 residues) of the GDH monomer has been deduced, and comparisons are made with reported amino acid sequences of GDH from other organisms.

Amino Acid Sequence↗

Nucleotide sequence of the gene for heat-stable enterotoxin II of Escherichia coli.

Previously, the gene for heat-stable enterotoxin II (STII) has been mapped by transposon Tn5 insertion mutagenesis in the chimeric R-Ent plasmid pCG86 (Mazaitis, A. J., R. Maas, and W. K. Maas, J. Bacteriol. 145:97-105, 1981). DNA segments containing this gene were cloned from the wild-type and STII-insertion-mutant plasmid. The position of the Tn5 insertion was determined, and a 530-base-pair-long segment of the wild-type plasmid corresponding to the Tn5 insertion site was sequenced. An open reading frame for the STII gene was identified and is characterized by typical promoter and ribosome binding site sequences. The deduced STII structural gene codes for a protein 71 amino acids long, including a typical signal peptide of 23 amino acids and a mature protein of 48 amino acids. The size and overall structure of STII are similar to those of STI, but the amino acid compositions of the two heat-stable enterotoxins are completely different.

Amino Acids↗