Abstract An extracellular uricase producing bacterium (VITPCB5) was isolated from soil of the duck farm near Chidambaram, Tamilnadu, India and it was identified based on its 16S rRNA as Sphingobacterium thalpophilum. Uric acid was used as an effective inducer. The enzyme kinetics was studied using uric acid as a substrate. The Km and Vmax for the enzyme was found to be 0.28 mM and 0.92 μM/min ml, respectively. Maximum uricase production was observed when lactose was used as a carbon source. Among the nitrogen sources tested, urea gave the maximum uricase production. The enzyme was successfully purified using a weak cation exchange convective interaction media carboxy methyl (CIM-CM) monolith column with a recovery of 79.7% ± 0.1 and 14.2 ± 1.8-fold purification. The optimal reaction temperature of the enzyme was observed between 25 and 45°C. The pH optimum of the enzyme was 8.0. The enzyme activity was enhanced by copper and partially inhibited by calcium, iron, zinc and nickel ions. Treatment with ethylene diamine tetraacetic acid completely inhibited the enzyme activity. The in-gel trypsin digested peptides of 48-kDa uricase when analyzed using mass spectrometry, gave 32% sequence coverage with the uricase (30-kDa) from Cyberlindnera jadinii. © 2015 Elsevier Inc.

Jayaprakash N S

Centre for Bio-Separation and Technology

Vellore Campus

Ravichandran R

Hemaasri S

Cameotra S.S

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Protein Expression and Purification

Applied Biochemistry and Biotechnology

Purification of ß-glucosidases from Pichia etchellsii Using CIM Monolith Columns

Purified monoclonal antibodies (mAb) have been used in therapeutics and some analytical procedures. Purification of mAb by use of high-throughput anion-exchange methacrylate monolithic systems has been attempted in this work. Monolithic macroporous convective interaction media (CIM) with diethylaminoethyl (DEAE) and ethylene diamine (EDA) as anion-exchange ligands were used and evaluated for purification of anti-glycophorin-A IgG1 mouse mAbs from cell culture supernatant (CCS) after precipitation with 50% ammonium sulfate. The adsorption and elution of mAb from the CCS on CIM-DEAE and CIM-EDA disks were studied with three different buffer systems, acetate, MOPS (3-(N-morpholino) propanesulfonic acid), and Tris, to study the effect of the nature of buffer ions and to find the optimum buffer conditions for purification of mAb. The optimum buffers for purification of mAb using CIM-DEAE and CIM-EDA were 50 mM acetate buffer, pH 5.1 and 20 mM Tris buffer, pH 8.0, respectively. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA) showed the antibody fractions obtained were highly pure, with high antigen-binding efficiency. High specific activity with purification factors of 130 ± 34 (unretained fraction with acetate buffer) and 74 ± 13 (fraction eluted with Tris buffer containing 0.6 M NaCl) was obtained for IgG1 using the CIM-DEAE and CIM-EDA disks, respectively. The results indicate that rapid separation and efficient recovery of high-purity anti-glycophorin-A mAbs could be achieved by use of anion-exchange CIM disks. © 2010 Vieweg+Teubner Verlag | Springer Fachmedien Wiesbaden GmbH.

Chromatographia

Purification of Monoclonal Antibodies from Cell-Culture Supernatant by Use of Anion-Exchange Convective Interaction Media (CIM) Monolithic Columns

The IgM antibodies from rheumatoid arthritis (RA) patients' sera were screened for peptide hydrolyzing activity. Recovery of structurally intact IgM antibodies (Abs), in a single step, was achieved using a weak anion-exchange methacrylate monolith disk. The IgM Abs from patients' sera hydrolyzed the Pro-Phe-Arg-4-methyl-coumaryl-7-amide (PFR-MCA) substrate appreciably compared to the healthy donors. The apparent K(m) values of IgM Abs from patients' sera were between 0.4 and 0.7 mM. Furthermore, IgM Abs displayed 5 to 10-folds greater proteolysis activity than IgG Abs, recovered from the same pathological serum. The proteolysis activity, as a function, was found to be independent of IgM-RF titer value. Affinity labeling approach targeted at the catalytic site histidine was studied, using a specific irreversible inhibitor, N-α-tosyl-L-lysine chloromethyl ketone (TLCK). Despite modification of catalytic His, observation of serine protease like activity suggest presence of an atypical catalytic framework in a few pathological IgM Abs.

Fulltext

Journal of Molecular Recognition

Proteolysis activity of IgM antibodies from rheumatoid arthritis patients' sera: evidence of atypical catalytic site

Journal of Chromatography A

Characterization of metal chelate methacrylate monolithic disk for purification of polyclonal and monoclonal immunoglobulin G

Tropical Parasitology

An interview with Dr. Magda Azab

Purification and characterization of an extracellular uricase from a new isolate of Sphingobacterium thalpophilum (VITPCB5)

Journal	Data powered by TypesetProtein Expression and Purification
Publisher	Data powered by TypesetElsevier BV
ISSN	1046-5928
Open Access	0