Modified general affinity adsorbent for large-scale purification of penicillinases

Area of Science:

• Biochemistry
• Biotechnology
• Affinity Chromatography

Background:

• N-acetyl-D-(-)-penicillamine is a biospecific ligand for purifying Bacillus cereus beta-lactamase I.
• Previous methods used complex spacer arms, which were found to be inefficient due to ligand proximity hindering enzyme binding.

Purpose of the Study:

• To develop a simplified and more efficient affinity adsorbent for large-scale penicillinase purification.
• To optimize the spacer arm length and ligand density for improved binding capacity.

Main Methods:

• Direct activation of Sepharose 4B matrix with divinyl sulphone to shorten the spacer arm.
• Coupling of N-acetyl-D-(-)-penicillamine ligand to the activated matrix.
• Batch purification of penicillinases from various bacterial sources.
• Regeneration of the affinity adsorbent through reacetylation.

Main Results:

• Shortening the spacer arm by direct matrix activation yields a satisfactory affinity material.
• Optimal ligand incorporation is 15 µmol per ml of Sepharose 4B, achieving maximum binding capacity.
• The simplified adsorbent efficiently purifies penicillinases from diverse bacterial sources via batch method without enzyme pre-concentration.
• The affinity adsorbent's binding capacity can be regenerated through multiple reacetylation cycles.

Conclusions:

• A simplified, stable, second-generation affinity adsorbent using N-acetyl-D-(-)-penicillamine with a shortened spacer arm is effective for large-scale penicillinase purification.
• This optimized adsorbent offers improved efficiency and reusability, making it suitable for industrial applications.
• The method allows for homogeneous purification of penicillinases from various bacterial sources.