Penicillin acylase has vital role in the degradation of penicillin into the 6-aminopenicillanic acid (6-APA) and the side chain organic acid. This property of penicillin acylase has been exploited commercially for large-scale production of 6-APA, which is a key intermediate in the manufacture of semi-synthetic penicillin. Due to worldwide demand of semi-synthetic penicillin, production of 6 APA has been increased upto 7000 tones in recent year. 6APA is produced in low concentration by penicillium chrysogenum when the organism is grown in medium, without addition of phenyl acetic acid as precursor. But this method is very costly and hence 6 APAase produced by splitting off the acetyl side chain of microbially produced penicillin G with enzyme penicillin acylase:- Penicillin G---------Phenyl acetic acid+6 APA
Special features of types of penicillin acylase
Type I -also called fungal type- This type of penicillin acylase split phenoxymethyl penicillin and produced by P.chrysogenum, aspergillus ochraceus, cephalosporin sp.
This is extracellular, have pH optimum-10, temp optimum-50oC
Type II -called bacterial type are produced by aerobacter, corneybacterium with temp optimum-40o C and pH optimum-8
Essential steps of production of penicillin acylase from escherichia coli:
1. E.coli are used almost exclusively for 6 APA production.
2. Production strains are mutant of e.coli ATCC 11505 and escherichia coli ATCC 9637
3. Production is induced by addition of phenyl acetic acid which act as precursor for the production of P.acylase.
4. Glucose represses the enzyme production and should be present in small quantity in a culture. High partial pressure and anaerobic condition also suppresses enzyme production.
5. Nutrient medium consists of 2% corn steep water at pH-7.0.The inoculum consists of 0.25% of an 18- hour preculture. To induce enzyme formation, after 8 hour of fermentation at 24o C, 0.1% of sterile ammonium phenyl acetate solution is added at hourly interval for next 13 hours.
6. The cell are concentrated 20 fold on a separator and the enzyme is then release by use of pressure dis integrator.
7. Enzyme yield in commercial production has been subsequently increased by the use of recombinant genetic technique for e.g. cloning a penicillin acylase gene on the multi-copy plasmid can improve the production by 28 fold.
About Author / Additional Info:
Author name and address:
Dr. Kirti Rani Sharma,
Assistant Professor (II),
Amity Institute of Biotechnology,
Amity University Uttar Pradesh, Noida
Sec-125, Gautam Buddha Nagar, Noida-201303 (UP), India.
Email ID: email@example.com, Kirtisharma2k@rediffmail.com