Abstract: A process for production of insulin or insulin analogs by expression of Insulin or Insulin analogs through an expression vector in a host cell is provided. The expression vector includes a leader peptide of SEQ ID NO 3; a nucleotide sequence encoding an affinity tag linked to C-terminal end or N terminal end of nucleotide sequence of the leader peptide; and a nucleotide sequence encoding for a cleavage site ligated to nucleotide sequence of the leader peptide through nucleotide sequence encoding the affinity tag.

Abstract: An expression vector for production of a recombinant protein in a host cell is provided. The expression vector includes a nucleotide sequence of Sequence ID No 2 encoding for a leader peptide of sequence ID No 3.

Abstract: An expression vector for production of a recombinant protein in a host cell is provided. The expression vector includes a nucleotide sequence of Sequence ID No 2 encoding for a leader peptide of sequence ID No 3.

Abstract: A process for production of insulin or insulin analogues by expression of Insulin or Insulin analogues through an expression vector in a host cell is provided. The expression vector includes a leader peptide of SEQ ID NO 3; a nucleotide sequence encoding an affinity tag linked to C-terminal end or N terminal end of nucleotide sequence of the leader peptide; and a nucleotide sequence encoding for a cleavage site ligated to nucleotide sequence of the leader peptide through nucleotide sequence encoding the affinity tag.

Abstract: A machine or apparatus for refolding a protein of interest produced recombinantly in a host cell in form of inclusion bodies is provided. The apparatus includes an inclusion bodies (IB) solubilisation tank to solubilise the inclusion bodies; a plurality of refolding vessels or reactors arranged in series to receive a refolding feed; a first tank connected to the IB solubilisation tank to hold diafiltration buffer or agent; a first diafiltration cartridge having at least one permeate end and one retentate end, connected to the IB solubilisation tank, through a first retentate end to feed the refolding feed to the IB solubilisation tank; a second tank, connected to the first permeate end of the diafiltration cartridge to receive and recycle the refolding buffer and each of the refolding vessels, for supplying refolding buffer or agent to each of the refolding vessels.

Abstract: A process for obtaining a refolded recombinant protein from an unfolded recombinant protein present in inclusion bodies isolated from wet cells harvested from a cell culture is provided. The process includes a) reducing the inclusion bodies by treating the inclusion bodies with a reducing buffer, to obtain reduced inclusion bodies; b) obtaining stable first intermediate state I1 of the unfolded recombinant protein present in the reduced inclusion bodies; and c) refolding the stable first intermediate state I1 of the unfolded recombinant protein, present in the reduced inclusion bodies, in refolding buffer to obtain a second intermediate state I2 that folds to produce the refolded recombinant protein.

Abstract: A process of refolding a recombinant protein from inclusion bodies (IBs) formed inside a host cell, is provided. The process includes homogenising a wet cells slurry to obtain a cell lysate; incubating the cell lysate with a reducing agent to obtain a reduced cell lysate; isolating reduced IBs from the reduced cell lysate to obtain isolated IBs; solubilising the isolated IBs with a denaturing agent to obtain solubilised IBs; and subjecting the solubilised IBs to a unit process of refolding to obtain a refolded recombinant protein.