Thematic collection: This article is part of the ‘Early Career Researchers’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research

On January 15, 1915, the first issue of PNAS, the official “organ of publication” of the National Academy of Sciences, appeared in print. It was, in some ways, a less than propitious time to launch a journal—just a little more than seven months after the start of what ultimately became...

In our computational study, we use molecular simulations to substantiate a hypothetical mechanism for glycosidic bond cleavage in the presence of a single catalytic acid at the active site of the mutant D10N HiCel45A. In addition to discussing this plausible mechanism from the context of structurally related MltA lytic transglycosylase and subfamily C GH45s, we also suggest the implications of the plausible mechanism for our current understanding of the action of expansins and lytic transglycosylases. As correctly pointed out by Professor Cosgrove (1), there is large body of evidence, a significant portion of which was regrettably not discussed in our paper, that suggests that expansins are incapable of lytic action on polysaccharide substrates. Whereas these insights do not change the results or the conclusions of our article, we would like to thank Professor Cosgrove for these additional insights. In particular, our main point with respect to expansins is that our results suggest the possibility that expansins are capable of nonhydrolytic lytic activity. Our intention was not to suggest this was the mechanism of expansins, but that it should be considered based on our results and the similarity of the active sites.The molecular mechanisms of how expansins enable cell wall expansion remains to be fully understood. Whereas our proposed mechanism resulting in the formation of the 1,6-anhdro product might be found in expansins and might contribute to the mode of action of expansins, we would like to emphasize that the intent of this study was only to suggest this as a...

From their simulations of endoglucanase Cel45A, Bharadwaj et al. (1) propose that structurally related expansins and MltA may cut glycan backbones without generating reducing ends. This is tenable for MltA, a peptidoglycan lytic transglycosylase whose action produces nonreducing 1,6-anhydro products, but is untenable for expansins.Expansins loosen plant cell walls and induce wall expansion. Contrary to the assertion by Bharadwaj et al., the conclusion that expansins are not lytic is not merely based on lack of new reducing ends but is supported by multiple (negative) tests for polysaccharide cleavage that do not rely on detection of reducing ends. At least eight studies with three divergent groups of expansins document this point. For instance, α-expansin did not reduce the viscosity of various wall polysaccharide solutions, an endolytic assay that does not rely on measuring reducing ends (e.g. see Ref. 2 and other studies).Walls treated with α-expansin did not release saccharide fragments, measured by pulsed amperometric detection, which can detect nonreducing saccharides (3).In the case of β-expansins, protein treatments did not cleave the backbones of a wide range of dye-coupled cross-linked wall polysaccharides; nor did they cleave backbones of polysaccharides extracted from plant cell walls, measured by gel permeation chromatography (4).For five microbial expansins, tests with a range of dye-coupled cross-linked polysaccharides likewise did not detect lytic activity (e.g. see Ref. 5). Thus, extensive published evidence argues against lytic action by expansins, as proposed by Bharadwaj (1), and attempts to identify 1,6-anhydro products seem unlikely to succeed.

Clinical and Vaccine Immunology (CVI) will merge with the American Society for Microbiology (ASM) open-access journal mSphere in January 2018. We commemorate this transition by exploring the history of CVI and that of its predecessor, Clinical and Diagnostic Laboratory Immunology (CDLI), and by acknowledging their contributors. Research on vaccines, clinical immunology, and clinical diagnostic immunology published through mSphere will be available without restrictions to an ever-larger audience, which will expedite progress in the field. ASM remains committed to supporting its members and the research community by facilitating the dissemination of scientific knowledge in these important areas.

Annelies Wouters, Jan-Pieter Ploem, Sabine A. S. Langie, Tom Artois, Aziz Aboobaker, and Karen Smeets

Pluripotent stem cells hold great potential for regenerative medicine. Increased replication and division, such is the case during regeneration, concomitantly increases the risk of adverse outcomes through the acquisition of mutations. Seeking for driving mechanisms of such outcomes, we challenged a pluripotent stem cell system during the tightly controlled regeneration process in the planarian Schmidtea mediterranea. Exposure to the genotoxic compound methyl methanesulfonate (MMS) revealed that despite a similar DNA-damaging effect along the anteroposterior axis of intact animals, responses differed between anterior and posterior fragments after amputation. Stem cell proliferation and differentiation proceeded successfully in the amputated heads, leading to regeneration of missing tissues. Stem cells in the amputated tails showed decreased proliferation and differentiation capacity. As a result, tails could not regenerate. Interference with the body-axis-associated component β-catenin-1 increased regenerative success in tail fragments by stimulating proliferation at an early time point. Our results suggest that differences in the Wnt signalling gradient along the body axis modulate stem cell responses to MMS.

Despite the importance of the Bering Sea for subarctic oceanography and climate, relatively little is known of the foraminifera from the extensive Aleutian Basin. We report the occurrence of modern deep-water agglutinated foraminifera collected at seven sites cored during Integrated Ocean Drilling Program (IODP) Expedition 323 in the Bering Sea. Assemblages collected from core-top samples contained 32 genera and 50 species and are described and illustrated here for the first time. Commonly occurring species include typical deep-water Rhizammina, Reophax, Rhabdammina, Recurvoides and Nodulina. Assemblages from the northern sites also consist of accessory Cyclammina, Eggerelloides and Glaphyrammina, whilst those of the Bowers Ridge sites consist of other tubular genera and Martinottiella. Of the studied stations with the lowest dissolved oxygen concentrations, the potentially Bering Sea endemic Eggerelloides sp. 1 inhabits the northern slope, which has the highest primary productivity, and the potentially endemic Martinottiella sp. 3 inhabits Bowers Ridge, which has the lowest oxygen concentrations but relatively low annual productivity. Martinottiella sp. 3, with open pores on its test surface, has previously been reported in Pliocene to Recent material from Bowers Ridge. Despite relatively small sample sizes, ecological constraints may imply that the Bering Sea experienced high productivity and reduced oxygen at times since at least the Pliocene. We note the partially endemic nature of the agglutinated foraminiferal assemblages, which may at least in part be due to basin restriction, the geologically long time period of reduced oxygen, and high organic carbon flux. Our results indicate the importance of gathering further surface sample data from the Aleutian Basin.

Competition ushers in new era to recognise the country’s standout real estate projects and senior leaders.

An image-editing program designed by researchers at Abode uses AI to let you quickly transform the shape of objects in images and change the lighting

Choose soft and cosy or short and sassy. Staying in gives you a great excuse to wear PJs all day

Staff of the magazine that kicked off the French New Wave say its new elite owners pose a threat to editorial independence

The mass resignation of the staff of Cahiers du Cinéma, the film journal that launched the French New Wave, has reignited debate in France about the possibility of critical independence in a society whose major stakeholders frequently operate in several spheres.

On Thursday, the 15 staff writers and editors announced their resignation, saying they believed its new owners posed a threat to the magazine’s cherished independence.

The speed limit on Spadina Crescent from Avenue H to Windsor Street should be reduced to 40km per hour, writes Don Greer.

Justin Bieber discussed his experiences during the latest episode of his and wife Hailey's Facebook Watch series, The Biebers on Watch.

On a ship frozen in the Arctic, scientists have spent all winter to shed light on exactly how the world is changing

Chipotle Mexican Grill Inc has secured a new year-long $600 million revolving credit line, a regulatory filing showed https://bit.ly/2SOtm6L on Friday, as the restaurant chain looks to deal with the fallout from the COVID-19 pandemic.

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The Duke and Duchess of Sussex have told four new newspaper groups – The Mirror, The Sun, The Daily Mail and Daily Express – they are no longer co-operating with them.

Thank early May bank holiday means payments will be disrupted

On the criteria for a claimant to be looking for work being paused for three months, Ms Coffey said: "We do however want claimants to continue to look for work wherever they are able to do so."

There are decisions being made right now that could have an effect on global populations for generations to come. As part of this project, we commissioned an artist to investigate some of the themes raised in the podcasts. This work of fiction imagines a future where gene editing has become mainstream and discusses the moral, ethical and political divides that this might create

Smartphones can be used to digitally trace Covid-19. But not if the public don’t download an app over privacy fears – or find it won’t work on their device

The idea of the NHS tracing app is to enable smartphones to track users and tell them whether they interacted with someone who had Covid-19. Yet this will work only if large proportions of the population download the app. No matter how smart a solution may appear, mass consent is required. That will not be easy. Ministers and officials have failed to address the trade-offs between health and privacy by being ambiguous about the app’s safeguards.

Instead of offering cast-iron guarantees about the length of time for which data would be held; who can access it; and the level of anonymity afforded, we have had opacity and obfuscation. It is true that we are dealing with uncertainties. But without absolute clarity about privacy the public is unlikely to take up the app with the appropriate gusto.

The chance to put biodiversity and the environment at the heart of recovery from the pandemic should not be squandered

One night in April, birdwatchers from around Britain stepped outside their doors and listened intently to something most of them had never experienced before: the fluting, mysterious, melancholy cry of the common scoter on the wing.

Flocks of these dusky sea ducks were beating their way over Britain on their long migratory journey towards their Arctic breeding grounds, easily audible to the naked ear. The first great wave was heard on the Wirral before being picked up in the Peak District, and at last by the Humber. A second wave was made out as flocks made their way along the line of Hadrian’s wall, from the Solway Firth in the west to Northumberland in the east. A third wave flew above listeners from the Severn estuary to the Wash. The birds were heard in urban Blackburn, Stalybridge, Bristol and London. It was thanks to social media that so many listeners were alert to the birds’ progress – and thanks to the silence of lockdown that they could be heard.

Letter seeks to dispel view that Prof Neil Ferguson was single architect of lockdown idea

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A group of leading UK scientists have insisted that the scientific basis for the coronavirus lockdown is the work of a large group of experts, and that epidemiologist Prof Neil Ferguson is just one voice among many.

In a letter co-ordinated by Dr Thibaut Jombart, an associate professor at the London School of Hygiene and Tropical Medicine, more than 25 prominent scientists said debates after Ferguson’s “individual error” – in which he flouted lockdown rules by receiving visits at home from his lover – had amplified a misconception that he alone persuaded the government to change policy.

Posted this to collector's edition topic, but figured I'd give everyone a heads up:

https://www.gamestop.com/video-games/playstation-4/games/products/persona-5-royal-phantom-thieves-edition/11098855.html

Price is "on sale" for free until May 10th, so claim it while you can.

PS4: https://store.playstation.com/en-us/product/UP0700-CUSA04924_00-PACMANCE2BUNDLE0

Xbox One: https://www.microsoft.com/en-us/p/pac-man-championship-edition-2/bpv04qgbn8j8#activetab=pivot:overviewtab

Steam: https://store.steampowered.com/app/441380/PACMAN_CHAMPIONSHIP_EDITION_2/

This is apparently Bandai-Namco's way of helping keep people entertained while stuck at home amidst the COVID stuff.

A white-knuckle tale of transgression and transformation, 'Revenge' gloriously blurs the lines of vengeance and survival while simultaneously delivering a ferocious dissection of gender and genre. MyMovies, trailer, 2020, Suspense, Coralie Fargeat, Kevin Janssens, Matilda Lutz

And let's move beyond the tiresome ideological battle lines of “private bad, public good.” It's not that simple.