Matthew McCallum

Separation of Pseudomonas aeruginosa type IV pilus-dependent twitching motility and surface-sensing responses | mBio The ability of bacteria to sense and respond to contact with surfaces is important for triggering changes in secondary messenger levels and gene expression, leading to the formation of biofilms and in...

New paper! Specific PilA and PilY1 sequences make PilU dispensable for T4P-dependent twitching motility in P. aeruginosa. However, most suppressors still had high cAMP levels from loss of PilU, showing that motility and surface sensing responses can be uncoupled.🧐 ⏩ journals.asm.org/doi/10.1128/...

Excited to be part of this collaboration with the Burrows lab exploring twitching and surface surface sensing by P. aeruginosa. This work further delineates a role for the T4P motor proteins and pili for surface sensing.
journals.asm.org/doi/10.1128/...
@asm.org

Potent neutralization of Marburg virus by a vaccine-elicited monoclonal antibody Marburg virus (MARV) is a filovirus that causes a severe and often lethal hemorrhagic fever. Despite the increasing frequency of MARV outbreaks, no vaccines or therapeutics are licensed for use in hum...

Outbreaks of Marburg virus (MARV) disease have been increasingly more frequent recently. Here we describe a prefusion-stabilized MARV GP and a best-in-class MARV neutralizing antibody!

Led by @aminaddetia.bsky.social with @virbiotechnology.bsky.social

@hhmi.org

www.biorxiv.org/content/10.1...

Phylogeny-driven design of broadly protective sarbecovirus receptor-binding domain nanoparticle vaccines Vaccines against emerging SARS-CoV-2 variants and sarbecoviruses with pandemic potential must elicit a robust humoral immune response in a population imprinted with the SARS-CoV-2 spike (S) protein. H...

Delighted to share our most recent work on designing broadly protective sarbecovirus vaccines and defining the path forward for other coronaviruses.

Led by @aminaddetia.bsky.social

@hhmi.org

www.biorxiv.org/content/10.1...

Conformational changes in the motor ATPase CpaF facilitate a rotary mechanism of Tad pilus assembly - Nature Communications The bacterial Tad pilus extends and retracts using a single bifunctional ATPase CpaF. Here, the authors employ cryo-EM, fluorescent microscopy, and AlphaFold modelling to propose how a rotary mechanis...

Thrilled to announce my first PhD publication in Nature Comms! We determined structures of the Tad pilus ATPase CpaF from Caulobacter. We use these structures to propose how CpaF employs a rotary mechanism of catalysis to drive Tad pilus assembly.
www.nature.com/articles/s41...

A natural experiment on the effect of herpes zoster vaccination on dementia - Nature Using a natural experiment that avoids common bias concerns, this study finds that the live-attenuated shingles vaccine reduced the probability of a new dementia diagnosis within a follow-up period of...

The vaccine against Shingles helps protect against dementia, results of a natural experiment, adding to prior evidence
"implications are profound"
New @nature.com
www.nature.com/articles/d41...
nature.com/articles/s41...

Deconvolution to restore cryo-EM maps with anisotropic resolution https://www.biorxiv.org/content/10.1101/2025.02.23.639707v1

Structure-based design of an immunogenic, conformationally stabilized FimH antigen for a urinary tract infection vaccine pubmed.ncbi.nlm.nih.gov/39970181/ #cryoEM

Multiple independent acquisitions of ACE2 usage in MERS-related coronaviruses Two coronaviruses related to MERS-CoV, which infect European Pipistrellus bats, have been found to use ACE2 as their receptor. These viruses target an ACE2 surface region distant from those recognized...

With participation of Jimin Lee, Jack Brown, Risako Gen, @dabiophysicist.bsky.social, Cameron Stewart in our lab & in collaboration with the labs of Huan Yan and Tyler Starr

www.cell.com/cell/fulltex...

Human naïve B cells recognize prepandemic influenza virus hemagglutinins Antibodies targeting the influenza hemagglutinin from potentially pandemic H5Nx viruses can be isolated from naïve individuals.

Our long-awaited study in collaboration with the Schmidt lab on H5Nx influenza recognition by naive B cells is out! #antibody #bcell #flu #avianflu #cryoEM

www.science.org/doi/10.1126/...

SARS-CoV-2 nsp1 mediates broad inhibition of translation in mammals SARS-CoV-2 nonstructural protein 1 (nsp1) promotes innate immune evasion by inhibiting host translation in human cells. However, the role of nsp1 in other host species remains elusive, especially in b...

Here, we show that SARS-CoV-2 nsp1 inhibits translation in a wide range of mammalian cells from known hosts (deer, mink, cat, dog,...) & unveils the architecture of a Rhinolophus bat ribosome with mRNA channel obstructed by nsp1!

Led by Risako Gen
@hhmi.bsky.social

www.biorxiv.org/content/10.1...

Repetitive injury induces phenotypes associated with Alzheimer’s disease by reactivating HSV-1 in a human brain tissue model Head injury may raise the risk of neurodegenerative disease by awakening a dormant virus.

www.science.org/doi/10.1126/...

Indeed - thank you David Goodsell for bringing science to life with art! Seeing the pilus motor featured is still my favourite grad school memory

doi.org/10.2210/rcsb...

Structure of the Pseudomonas aeruginosa PAO1 Type IV pilus
Finally out in PLOS Pathogens. Congrats Hannah Ochner and co-authors. @mrclmb.bsky.social

journals.plos.org/plospathogen...

Thanks, and yes that was a surprise. I remain optimistic that these antigens will present more uniquely prefusion epitopes, as it would appear so structurally, and therefore elicit enhanced immunity. In any case, now having an ability to isolate prefusion-specific antibodies will help moving forward

I couldn’t have done this work without the incredible mentorship of @veeslerlab.bsky.social

Our latest work stabilizing the gB fusion protein.

This paves the way for next-gen vaccines against Herpesviruses implicated in cancer, MS, and dementia.

🔗 www.biorxiv.org/content/10.1...

#herpesvirus #EBV #HSV #CMV #proteindesign #virology #immunology