Tag Archives: Christopher Ashwood

Understanding the role that sugars play

30 March 2018:

CNBP scientists Chris Ashwood (pictured) and Prof Nicki Packer at Macquarie University have shown that sugars with exactly the same chemical composition but slightly different structure break apart differently in their latest publication in the area of mass spectrometry. This work is their first step in automating sugar analysis, to understand the role sugars play in human disease.

Journal: Journal of The American Society for Mass Spectrometry.

Publication title: Discrimination of Isomers of Released N- and O-Glycans Using Diagnostic Product Ions in Negative Ion PGC-LC-ESI-MS/MS.

Authors: Christopher Ashwood, Chi-Hung Lin, Morten Thaysen-Andersen, Nicolle H. Packer.

Profiling cellular protein glycosylation is challenging due to the presence of highly similar glycan structures that play diverse roles in cellular physiology. As the anomericity and the exact linkage type of a single glycosidic bond can influence glycan function, there is a demand for improved and automated methods to confirm detailed structural features and to discriminate between structurally similar isomers, overcoming a significant bottleneck in the analysis of data generated by glycomics experiments. We used porous graphitized carbon-LC-ESI-MS/MS to separate and detect released N- and O-glycan isomers from mammalian model glycoproteins using negative mode resonance activation CID-MS/MS. By interrogating similar fragment spectra from closely related glycan isomers that differ only in arm position and sialyl linkage, product fragment ions for discrimination between these features were discovered. Using the Skyline software, at least two diagnostic fragment ions of high specificity were validated for automated discrimination of sialylation and arm position in N-glycan structures, and sialylation in O-glycan structures, complementing existing structural diagnostic ions. These diagnostic ions were shown to be useful for isomer discrimination using both linear and 3D ion trap mass spectrometers when analyzing complex glycan mixtures from cell lysates. Skyline was found to serve as a useful tool for automated assessment of glycan isomer discrimination. This platform-independent workflow can potentially be extended to automate the characterization and quantitation of other challenging glycan isomers.

Glycan identification and quantitation

21 September 2017:

Christopher Ashwood, CNBP PhD candidate, visited Ireland in September 2017, performing an oral presentation at the 16th Human Proteome Organisation World Congress with a presentation titled: “Open-glycomics: An open-access platform for software-assisted glycan identification and quantitation”.

He also visited the National Institute for Bioprocessing Research and Training (NIBRT) where he also presented his research.

Talk summary: Analysing glycomics data, the study of carbohydrates, is largely manual resulting in low throughput and can be subject to human error. Using a software package named Skyline, Chris has automated the most tedious parts of this data analysis and generated the data in a standard format for use by other glycomics researchers and bioinformaticians. Future research will standardise and automate this analysis further for application towards the currently booming biopharmaceutical industry.

Breaking apart sugars

9 March 2017:

CNBP scientists Chris Ashwood and Prof Nicki Packer at Macquarie University have shown alternative ways to break apart sugars, improving their characterisation in their latest publication in the area of mass spectrometry (Enhancing structural characterisation of glucuronidated O-linked glycans using negative mode ion trap higher energy collision-induced dissociation mass spectrometry).

The work was published online in the journal Rapid Communications in Mass Spectrometry on 9th March 2017 and was funded by the Australian Research Council Centre of Excellence for Nanoscale BioPhotonics.

CNBP researchers at National Proteomics Conference

Nicki Packer Low Res Edit 01257 February 2016:

The 21st Annual Lorne Proteomics Symposium, organized by the Australasian Proteomics Society, was held February 4th – 7th 2016 in Lorne, Victoria and was attended by CNBP members of the Macquarie Node, Nicolle Packer, Christopher Ashwood and Abdulrahman Shathili.

The symposium featured the latest developments in proteomics technologies and tools for the interpretation of proteomics outputs, and their application toward answering fundamental questions in biology. Invited speakers included the most cited person in the field of proteomics, Matthias Mann, as well as internationally renowned glycomics expert, Anne Dell. CNBP Chief Investigator Nicolle Packer was also an invited speaker at the event and presented a talk titled “Alterations in Glycosylation in Ovarian Cancer.”

Students Christopher Ashwood and Shathili Abdulrahman both presented posters describing results from the past year, with Christopher Ashwood being awarded a poster prize for his research on characterisation of novel protein-glycosylation using rarely used analytical techniques in the field of glycomics.

Symposium information can be found online.

CNBP at Chemical Proteomics Symposium

chris_ashwood-low-rez417 July 2015:

Macquarie University CNBP PhD candidate, Christopher Ashwood, gave a poster presentation at the 2015 Chemical Proteomics Symposium, held at the Children’s Medical Research Institute in Sydney, Australia.

Chris’ work demonstrated links between metabolite and glycomic analysis and was titled: “Effect of carbon source on the protein glycosylation pathway of Trichoderma reesei RUT-C30.” The presentation was based on a paper by Christopher Ashwood, Helena Nevalainen and Nicolle H. Packer.

The 2015 Chemical Proteomics Symposium covered a broad range of topics related to modern Medicinal Chemistry and Proteomics and featured a dedicated session on current and future challenges of bioinformatics in proteomics research.