Protein Technologies

Protein Technologies Ltd has the necessary skills and a full in-house suite of equipment for the production of all types of recombinant proteins from gene design to protein production to biophysical characterisation.

We offer protein expression, assay development, drug screening, protein stability studies, isotope labelling of proteins for NMR and cDNA library development services.

• Design and synthesis of constructs for optimized protein production and purification. These include codon optimisation, fusion tags (e.g. GFP, luciferases, MBP), addition of purification tags (His-tags, double-His tags, GST, etc) and protease cleavage sites

• DNA manipulation techniques including plasmid preparation, fragment subcloning and site directed mutagenesis

• Enhancement of functional properties (catalytic activity or stability) through directed engineering

• Protein expression in a range of expression systems (E. coli, Saccharomyces cerevisiae & Pichia pastoris)

• Determination of protein purity by SDS-PAGE, Western blotting and Mass Spectrometry

• Protein Production (1-20 litre scale up).

• Isotope labelling service with 15N and 13C for NMR studies.

• Stability of proteins with chemical denaturants using fluorescence as a probe for unfolding. Examples include urea & guanidinium hydrochloride equilibrium analysis.

• Thermal stability of proteins using fluorescence or Circular dichroism as structural probes.

• Circular dichroism (CD) probing the secondary and tertiary stucture of proteins. Analysis of folded structures, e.g. after chemical modification, lipase modification and inclusion body refolding.

• Oligomeric analysis of protein complexes using MALLS-SEC.

• LC-MS-ESI analysis of peptides and proteins (after proteolytic digestion). Identification of unknown protein bands in gels using MASCOT databases. PTL has a full suite of in-house equipment & skills for the production of all types of recombinant proteins including:

• Enhancement of functional properties through directed engineering

• DNA manipulation techniques including plasmid preparation, fragment subcloning and site directed mutagenesis

• Protein expression in a range of expression systems

• Purification

• De novo design

• Structure based combinatorial protein engineering (SCOPE)

• Bioinformatics & bioinformatic mining of sequence space

• Baculovirus, mammalian & algal expression systems

• Affinity analysis by means of Surface Plasmon Resonance (SPR) using Biacore technology. Applications include determination of Kd, antibody interactions, antibody profiling, protein-protein interactions and target-peptide binding assays

• Fluorescence kinetic (enzyme) and end-point assays: fluorescence intensity, time-resolved fluorescence (TRF) and fluorescence polarization assays (FP)

• Luminescence kinetic and end-point assays (luciferase/ luciferin)

• Absorbance based assays: e.g. NADP and p-nitrophenyl based assays

• HPLC enzyme substrate/ product quantitative assays ELISA design, development and testing of new ELISA assays; also for E. coli generated proteins

• Production of recombinant proteins for generation of antibodies

• Preparation of protein/peptide conjugates, labeling with enzymes, fluorescent probes and haptens

• Liquid-liquid / reaction-separation (LLRS) has the potential: (i) to convert batch bioprocesses into continuous bioprocesses; (ii) to effect cost reduction in, or dispense altogether with, the expensive down-stream processing steps of centrifugation, separation and purification, and (iii) to considerably simplify waste water handling in very large scale enzymatic processes.