Technologies – Fragment Screening Libraries
The development of fragment screening libraries could enhance the analysis and application of natural products for medicinal chemistry and drug discovery, according to Professor Ronald Quinn. This is another example of GRIDD’s determination to constantly seek out, trial and apply new techniques in the study of natural products for drug discovery.
In a paper entitled 'Capturing Nature's Diversity' and published in the peer-reviewed journal PLOS ONE, Professor Quinn and his co-authors propose a novel approach to reveal nature’s structural diversity for medicinal research and implementation.
"A lot of natural product drug discovery research is still being conducted in the same way as it has for decades; however fragment-based screening using small natural products is a modern, fast and highly efficient process," says Professor Quinn.
Another advantage of the approach is that a small library of compounds can represent a much larger proportion of natural products.
In their study, the Quinn team identified fragment-sized natural products from a known database, the Dictionary of Natural Products, and then investigated their structural diversity via atom type, atom function and analysis of chemical scaffold.
In total they presented 422 structural clusters from approximately 2800 natural products that could be applied in chemical biology and drug discovery research.
Professor Quinn contends these naturally-derived fragments could be used as the starting point for a highly diverse library with scope for further elaboration due to their minimal structural complexity.
Fragment-based screening broadens research scope, identifies and characterises specific physiological and disease processes, and modernises natural product discovery.
High Throughput Screening (HTS) and High Content Imaging (HCI)
- State-of-the-art lab automation and high content imaging platforms
- Experienced assay development team, with a focus on HTS and HCI
- Hit discovery through to lead optimisation
Professor Vicky Avery heads a team of highly skilled scientists undertaking High Throughput Screening (HTS) and High Content Imaging (HCI) within GRIDD. The objective is to support biomedical drug discovery research programmes spanning hit-to-lead to lead optimisation across a wide range of diseases.
The focus of the laboratory is biological-based drug discovery, inclusive of both basic and applied research. Emphasis is placed on assay design and development towards identifying and characterising novel molecules for the treatment of disease.
The facility is equipped with a suite of liquid handling robotics, sophisticated high content screening platforms and advanced data analysis and bioinformatics software solutions.
Numerous biochemical and cellular technologies are utilised throughout the screening process from assay development and validation through to lead optimisation. The team has extensive expertise in all stages of HTS and HCI and widespread industry collaboration experience. Compound management is supported by Compounds Australia co-located within GRIDD.
GRIDD combines world class HCI technology with advanced biological modelling to provide physiologically relevant and information-rich data for the discovery of novel therapies.
- Expertise in optimising assay biology (adapting bench top assays to high throughput formats amenable for HTS)
- Biologically relevant parasite based models suitable for HTS
- In vitro 3D cancer cell models mimicking the tumour micro-environment, established in micro-titre plate format for HCI
- High content phenotypic based cellular screening
- Developing custom image analysis and scripting protocols
FTMS – Drug discovery through mass spectrometry
GRIDD is unique in using Fourier Transform Mass Spectrometry (FTMS) for drug discovery screening. GRIDD’s FTMS infrastructure is funded by the Australian Research Council (ARC) and provides a rapid approach for early-stage drug discovery.
The Institute’s FTMS research has been independently recognised as among the most important drug discovery technology advances in recent years. Specifically, the Journal of Medicinal Chemistry identified the top drug discovery tools papers for 2015/2016 (J. Med. Chem. 2016, 59, 2192−2204). Number 1 on that list was the FTMS paper published by GRIDD’s Professor Sally-Ann Poulsen and her team members.
Sally-Ann notes that there is growing recognition of the benefits of FTMS, especially in early stage drug discovery, because the FTMS technology is unbiased, uses very little protein in comparison to other methods and can rapidly filter libraries of thousands of compounds to find those that are of further interest for drug discovery.
FTMS use at GRIDD
Professor Sally-Ann Poulsen introduced FTMS use for the study of protein-ligand complexes to Australia, and was one of the first researchers worldwide, and the first in Australia, to utilise native state mass spectrometry to screen fragments by the direct observation of protein-ligand complexes. This approach holds significant promise in addressing the pipeline problems of the Pharma industry.
Proteins are often the targets for drugs. One approach to discover new drugs is to identify chemicals, or small molecules, that interact with or bind to target proteins. Discovering which small molecules bind to a protein target is thus a critical first step in early-stage drug discovery. FTMS is a highly sensitive and unbiased approach that can be used to do just that - identify chemicals that bind to proteins.
How does it work? By “weighing” the protein before and after it is mixed with potential drug molecules. Imagine FTMS as a set of scales that measure (with exceptional accuracy) the mass of individual molecules. On the scales stands an elephant, representing a ‘heavy’ protein: the drug target. If a potential drug molecule binds to the protein, the FTMS detects an increase in mass of the ‘heavy’ protein because it has bound to a ‘very light’ drug molecule – like measuring the mass of an elephant holding an ice-cream. The FTMS instrument can differentiate this tiny mass difference – elephant empty-handed, versus elephant holding an ice-cream - and it is this tiny mass difference that provides the evidence needed to identify potential drug molecules.
- Expertise in native state mass spectrometry for intact protein analysis
- Initial assessment of the suitability of your protein target for fragment screening by native state mass spectrometry
- Fragment/small molecule screening campaign using native state mass spectrometry
- Qualitative and quantitative analysis of fragment/small molecule-protein binding
- High resolution mass spectrometry analysis of small molecules