A proteomic approach to investigating gene cluster expression and secondary metabolite functionality in Aspergillus fumigatus.

A combined proteomics and metabolomics approach was utilised to advance the identification and characterisation of secondary metabolites in Aspergillus fumigatus. Here, implementation of a shotgun proteomic strategy led to the identification of non-redundant mycelial proteins (n = 414) from A. fumigatus including proteins typically under-represented in 2-D proteome maps: proteins with multiple transmembrane regions, hydrophobic proteins and proteins with extremes of molecular mass and pI. Indirect identification of secondary metabolite cluster expression was also achieved, with proteins (n = 18) from LaeA-regulated clusters detected, including GliT encoded within the gliotoxin biosynthetic cluster. Biochemical analysis then revealed that gliotoxin significantly attenuates H2O2-induced oxidative stress in A. fumigatus (p>0.0001), confirming observations from proteomics data. A complementary 2-D/LC-MS/MS approach further elucidated significantly increased abundance (p<0.05) of proliferating cell nuclear antigen (PCNA), NADH-quinone oxidoreductase and the gliotoxin oxidoreductase GliT, along with significantly attenuated abundance (p<0.05) of a heat shock protein, an oxidative stress protein and an autolysis-associated chitinase, when gliotoxin and H2O2 were present, compared to H2O2 alone. Moreover, gliotoxin exposure significantly reduced the abundance of selected proteins (p<0.05) involved in de novo purine biosynthesis. Significantly elevated abundance (p<0.05) of a key enzyme, xanthine-guanine phosphoribosyl transferase Xpt1, utilised in purine salvage, was observed in the presence of H2O2 and gliotoxin. This work provides new insights into the A. fumigatus proteome and experimental strategies, plus mechanistic data pertaining to gliotoxin functionality in the organism

Spectrum of mutational signatures in T-cell lymphoma reveals a key role for UV radiation in cutaneous T-cell lymphoma

Funder: Galderma; doi: http://dx.doi.org/10.13039/501100009754Funder: NIHR-BRC Cambridge core grantFunder: National Institute for Health Research; doi: http://dx.doi.org/10.13039/501100000272Funder: NHS EnglandAbstract: T-cell non-Hodgkin’s lymphomas develop following transformation of tissue resident T-cells. We performed a meta-analysis of whole exome sequencing data from 403 patients with eight subtypes of T-cell non-Hodgkin’s lymphoma to identify mutational signatures and associated recurrent gene mutations. Signature 1, indicative of age-related deamination, was prevalent across all T-cell lymphomas, reflecting the derivation of these malignancies from memory T-cells. Adult T-cell leukemia-lymphoma was specifically associated with signature 17, which was found to correlate with the IRF4 K59R mutation that is exclusive to Adult T-cell leukemia-lymphoma. Signature 7, implicating UV exposure was uniquely identified in cutaneous T-cell lymphoma (CTCL), contributing 52% of the mutational burden in mycosis fungoides and 23% in Sezary syndrome. Importantly this UV signature was observed in CD4 + T-cells isolated from the blood of Sezary syndrome patients suggesting extensive re-circulation of these T-cells through skin and blood. Analysis of non-Hodgkin’s T-cell lymphoma cases submitted to the national 100,000 WGS project confirmed that signature 7 was only identified in CTCL strongly implicating UV radiation in the pathogenesis of cutaneous T-cell lymphoma

Irish Shipping Limited 1939-45 and its Influence on Irish Neutrality

The outbreak o f the second world war in Europe was an event which had been foreseen by many in Ireland, including the taoiseach Eamon de Valera, but had still been largely unprepared for. The country, which had been independent for less than twenty years, followed the only course o f action available to her given this lack o f preparedness and the political circumstances o f the time, neutrality. This policy was adopted for two reasons, firstly as the Irish defence forces were ill equipped to partake in a modern war with no airforce or anti-aircraft guns with which to defend the country, and secondly it was affirmation to a global audience o f Irelands sovereignty and the fact that Britain no longer dictated her foreign policy. This policy o f neutrality was fraught with risk and pitfalls for the Fianna Fail government though. Foremost among their problems was the issue o f importing essential supplies to the country during the period o f the emergency. Prior to the war Ireland had relied on foreign ships to carry a large percentage o f her raw materials. However, with the outbreak o f war, these ships were no longer in a position to serve Ireland. This problem was compounded by the fact that British resentment at Irish neutrality resulted in her refusing to ship supplies to Ireland or recognise Irish economic difficulties. In response to this desperate situation Irish Shipping Ltd was formed in March 1941. Irish Shipping was vital to the maintenance o f Irish neutrality, as without the vital imports the company carried, Ireland would have faced economic ruin. This fact was recognised by many o f the belligerent powers though and consequently Irish Shipping was used as a means by which to put pressure on the Irish government, in some instances in an effort to move the government from its neutral stance. The aim o f this thesis is therefore to examine the role Irish Shipping played in Irish neutrality and to examine the extent to which it was used by belligerent powers to pressurise the Irish policy o f neutrality