How long does it take for a cell to synthesize an enzyme?
In human cells it takes about 20 s to make a 20,000 dalton enzyme.

Assuming that the cells concerned are already making mRNA for the enzyme, there will be two main factors:

(1) The time taken to synthesize the polypeptide

(2) Any time taken to fold the protein

(If the enzyme is secreted from the cell there will also be the time taken for the protein to traverse the secretory pathway - perhaps you want to include this time - if so it could be 10's of minutes.)

Here I will focus on (1). What is the rate of polypeptide elongation?

For bacteria:


  Young &amp; Bremer (1976) Polypeptide-chain-elongation rate in Escherichia coli B/r as a function of growth rate Biochem. J. 160: 185-194


They quote values of:
17 s-1 for fast-growing cells
and 12 s-1 for slower-growing cells.

For yeast:


  Bonven &amp; Gullov (1979) Peptide chain elongation rate and ribosomal activity in Saccharomyces cerevisiae as a function of the growth rate. Mol. Gen. Genet. 170: 225-230


minimal glucose 9.3 s-1
minimal acetate 5.5 s-1

In human cells:


  Ramabhadran &amp; Thach (1981) Translational elongation rate changes in encephalomyocarditis virus-infected and interferon-treated cells. J. Virol. 39: 573-583


They measure a control value of 9.4 s-1 and quote (with citations) values of 9-10 s-1 in reticulocytes and CHO cells.

Let's use 9 s-1, and assume 110 daltons per amino acid

Then e.g. a 20.000 dalton enzyme (= 182 amino acids) requires 20 seconds.