Bacterial expression vector for enhanced protein secretion
Inventors
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-12325860-B2
Publication Date
2025-06-10
Expiration Date
Abstract
The invention provides a bacterial expression vector (100) comprising of a secretory signal sequence in tandem with DNA sequence encoding recombinant protein (103), wherein, the secretory signal sequence is a combination comprising of: a) at least one DNA sequence encoding a signal sequence (101) of gene selected from the group consisting of pelB, ompA, yebF, and ompF, and b) at least one DNA sequence encoding a carrier peptide (102) selected from the group consisting of Seq. ID 5 and 6 encoding truncated yebF.
Core Innovation
The invention describes a bacterial expression vector, identified as SEQ ID: 13 (pBacSec-LC), for enhanced secretion of recombinant protein by host bacterial cells. The expression vector includes a DNA sequence encoding the amino acid sequence of SEQ ID NO: 12, a secretory signal peptide of the gene ompF, and a DNA sequence encoding a truncated YebF peptide of SEQ ID NO: 8.
The secretory architecture uses a tandem secretory signal combining an ompF-derived signal peptide and a truncated yebF carrier peptide. The vector further includes inducible promoter elements and regulatory features such as lac/tac promoter elements and an RBS, together with a recombinant protein cassette and affinity tags.
The vector provides quantified recombinant protein secretion performance, including a yield of 0.5 g/L in one hour and 5 g/L in six hours. The provided results include secretion observed for peptides in a 5–20 kDa range, and comparisons of carrier peptide variants, including mutation of carrier peptide Cys14 to Ala, intended to reduce dimerization/inclusion-body formation and to improve or maintain secretion behavior under reducing versus non-reducing conditions.
Claims Coverage
The independent claim clm-00001 covers a single bacterial expression vector defined by specific sequence identifiers (SEQ ID: 13) and by the presence and arrangement of specific secretory signal elements. It further requires quantitative secretion/yield performance at one hour and six hours, specifying inventive features comprising the ompF-derived secretory signal peptide and the truncated YebF peptide carrier peptide encoded by particular sequence identifiers.
Bacterial expression vector consists of SEQ ID: 13
A bacterial expression vector for enhanced secretion of recombinant protein, wherein the bacterial expression vector consists of SEQ ID: 13.
Tandem secretory signal comprising ompF signal peptide and truncated YebF peptide
The expression vector comprises a DNA sequence encoding amino acid sequence of SEQ ID NO: 12, a secretory signal peptide of the gene ompF, and a DNA sequence of SEQ ID No: 6 encoding a truncated YebF peptide of SEQ ID NO: 8.
Quantitative secretion yield requirements
The expression vector provides a yield of recombinant protein of 0.5 g/L in one hour and 5 g/L in six hours.
Overall, the claim scope is directed to a specific bacterial expression vector (SEQ ID: 13) that includes a defined secretory signal arrangement using an ompF-derived signal peptide together with a truncated YebF peptide encoded by defined sequence identifiers, and that meets specified recombinant protein yield performance at one hour and six hours.
Stated Advantages
Enhanced secretion of recombinant protein by host bacterial cells.
Provides a recombinant protein yield of 0.5 g/L in one hour and 5 g/L in six hours.
Documented Applications
Enhanced secretion of recombinant proteins in host bacterial cells, including secretion performance evaluated using a Gaussia luciferase assay and secretion observed for peptides in the 5–20 kDa range.
Interested in licensing this patent?