Greg Harrison
@bactophile.bsky.social
Postdoc at Tufts University
Studying C. difficile 🔬
Chicago > St. Louis > Boston
👨🔬🪴📚🍷🏳️🌈
Studying C. difficile 🔬
Chicago > St. Louis > Boston
👨🔬🪴📚🍷🏳️🌈
Reposted by Greg Harrison
Are you a graduate student or postdoc who wants to apply your science to policy?
The Gulf Research Program’s Science Policy Fellowship provides experience for one year on the staff of federal, state, local, NGO in the Gulf region and impt networking.
www.nationalacademies.org/programs/GUL...
The Gulf Research Program’s Science Policy Fellowship provides experience for one year on the staff of federal, state, local, NGO in the Gulf region and impt networking.
www.nationalacademies.org/programs/GUL...
Gulf Research Program Science Policy Fellowships
The Gulf Research Program’s Science Policy Fellowship helps scientists hone their skills by putting them to practice for the benefit of Gulf Coast communities and ecosystems. Fellows gain first-hand e...
www.nationalacademies.org
January 15, 2026 at 8:14 PM
Are you a graduate student or postdoc who wants to apply your science to policy?
The Gulf Research Program’s Science Policy Fellowship provides experience for one year on the staff of federal, state, local, NGO in the Gulf region and impt networking.
www.nationalacademies.org/programs/GUL...
The Gulf Research Program’s Science Policy Fellowship provides experience for one year on the staff of federal, state, local, NGO in the Gulf region and impt networking.
www.nationalacademies.org/programs/GUL...
Reposted by Greg Harrison
A single DNA methylation site regulates cell fate during Clostridioides difficile sporulation www.biorxiv.org/content/10.6...
A single DNA methylation site regulates cell fate during Clostridioides difficile sporulation
DNA methylation is a widespread phenomenon in bacteria that can regulate gene expression, although the mechanisms underlying this epigenetic regulation are often poorly understood. In Clostridioides d...
www.biorxiv.org
January 2, 2026 at 1:59 PM
A single DNA methylation site regulates cell fate during Clostridioides difficile sporulation www.biorxiv.org/content/10.6...
Congratulations Ruth!!! Such exciting news!! 🥳🥳
December 20, 2025 at 12:53 AM
Congratulations Ruth!!! Such exciting news!! 🥳🥳
Reposted by Greg Harrison
And check out the accompanying paper from the Grangeasse lab: www.nature.com/articles/s41...
Streptococcus pneumoniae S protein activates PBP1a to regulate peptidoglycan remodelling and cell division - Nature Microbiology
S protein interacts with and activates PBP1a during cell division, as part of a larger GpsB-associated multiprotein complex that coordinates peptidoglycan remodelling in Streptococcus pneumoniae.
www.nature.com
December 19, 2025 at 10:31 AM
And check out the accompanying paper from the Grangeasse lab: www.nature.com/articles/s41...
Reposted by Greg Harrison
December 19, 2025 at 10:31 AM
Reposted by Greg Harrison
Calling all postdoctoral women scientists in microbiology! We're here to support you; receive up to $2,000 to travel to a meeting, visit another laboratory or take a course to enhance your research skills. Check eligibility and apply now: asm.social/2Jh
December 10, 2025 at 7:01 PM
Calling all postdoctoral women scientists in microbiology! We're here to support you; receive up to $2,000 to travel to a meeting, visit another laboratory or take a course to enhance your research skills. Check eligibility and apply now: asm.social/2Jh
Reposted by Greg Harrison
indeed, 𝘙𝘶𝘨𝘰𝘴𝘪𝘵𝘢𝘭𝘦𝘢 𝘰𝘳𝘺𝘻𝘢𝘦 looke like fusilli, which are notably better at holding on salsa di pomodoro than spaghetti... and as pasta addicts, we fell instantly in love with the shape of this newly described alphaproteo from the Rhizobiales 🤭
#MicroSky
#MicroSky
December 10, 2025 at 7:52 PM
indeed, 𝘙𝘶𝘨𝘰𝘴𝘪𝘵𝘢𝘭𝘦𝘢 𝘰𝘳𝘺𝘻𝘢𝘦 looke like fusilli, which are notably better at holding on salsa di pomodoro than spaghetti... and as pasta addicts, we fell instantly in love with the shape of this newly described alphaproteo from the Rhizobiales 🤭
#MicroSky
#MicroSky
Congratulations Jeff!!
December 3, 2025 at 12:18 AM
Congratulations Jeff!!
Reposted by Greg Harrison
There's just over 2 weeks left to apply for a fully funded PhD studentship with us working on C. difficile vancomycin resistance. Two more studentships - linked in the thread below - close in early January
November 19, 2025 at 1:45 PM
There's just over 2 weeks left to apply for a fully funded PhD studentship with us working on C. difficile vancomycin resistance. Two more studentships - linked in the thread below - close in early January
Reposted by Greg Harrison
Three German universities offering post-docs for researchers "who cannot conduct or continue their work in the USA appropriately because of actual political pressure. "
www.uni-konstanz.de/zukunftskoll...
www.uni-konstanz.de/zukunftskoll...
Early Career Rescue Fellowship
www.uni-konstanz.de
November 11, 2025 at 7:10 PM
Three German universities offering post-docs for researchers "who cannot conduct or continue their work in the USA appropriately because of actual political pressure. "
www.uni-konstanz.de/zukunftskoll...
www.uni-konstanz.de/zukunftskoll...
Reposted by Greg Harrison
The 5th of 6 faculty positions in UNC Biology is posted. We're working with the @ncbg.bsky.social to fill a joint position as Director of the UNC Herbarium at @ncbg.bsky.social and as Associate Professor within the Department of Biology (BIOL). Please share 1/n
unc.peopleadmin.com/postings/308...
unc.peopleadmin.com/postings/308...
Associate Professor & Director of NCBG Herbarium
This is a research, teaching, and public service position at the University of North Carolina at Chapel Hill, serving jointly as Herbarium Director at the North Carolina Botanical Garden (NCBG) and as...
unc.peopleadmin.com
November 6, 2025 at 11:36 AM
The 5th of 6 faculty positions in UNC Biology is posted. We're working with the @ncbg.bsky.social to fill a joint position as Director of the UNC Herbarium at @ncbg.bsky.social and as Associate Professor within the Department of Biology (BIOL). Please share 1/n
unc.peopleadmin.com/postings/308...
unc.peopleadmin.com/postings/308...
While it’s still unclear how C diff PBP1 evolved this specific function, we have found several key features of this enzyme and identified a new C diff divisome protein (PBP3). Most excitingly, we now have some clues to latch onto as we continue trying to unravel this mystery! 😄
October 28, 2025 at 1:25 AM
While it’s still unclear how C diff PBP1 evolved this specific function, we have found several key features of this enzyme and identified a new C diff divisome protein (PBP3). Most excitingly, we now have some clues to latch onto as we continue trying to unravel this mystery! 😄
Tracking down the aberrant septa phenotype, we discovered that a non-essential orphan class B PBP called PBP3 plays a non-catalytic regulatory role in promoting PBP1 function (and causes TPase* PBP1 to synthesize too many septa) likely by over-activating PBP1’s glycosyltransferase activity
October 28, 2025 at 1:25 AM
Tracking down the aberrant septa phenotype, we discovered that a non-essential orphan class B PBP called PBP3 plays a non-catalytic regulatory role in promoting PBP1 function (and causes TPase* PBP1 to synthesize too many septa) likely by over-activating PBP1’s glycosyltransferase activity
Through our structure-function analysis, we surprisingly discovered that while the transpeptidase activity of PBP1 is required for C diff growth, the bacteria could still form septa and divide. They actually formed too many septa! And often in the wrong location 🧐
October 28, 2025 at 1:25 AM
Through our structure-function analysis, we surprisingly discovered that while the transpeptidase activity of PBP1 is required for C diff growth, the bacteria could still form septa and divide. They actually formed too many septa! And often in the wrong location 🧐
We found a domain that we call the GI domain that is critical to PBP1 function and shared with orthologs in some G+ anaerobes. Species with a GI domain in their PBP1 orthologs occupy a range of niches from the gut, oral cavity, to the vaginal tract. Some even live in marine mud and deep-sea vents!
October 28, 2025 at 1:25 AM
We found a domain that we call the GI domain that is critical to PBP1 function and shared with orthologs in some G+ anaerobes. Species with a GI domain in their PBP1 orthologs occupy a range of niches from the gut, oral cavity, to the vaginal tract. Some even live in marine mud and deep-sea vents!
Class A PBPs like PBP1 are not known to drive cell division in other bacteria. So we set out to determine how PBP1 evolved to take on this very important job. To begin to tackle this question, we used CRISPRi-compatible trans-complementation to conditionally express mutant variants of PBP1 in C diff
October 28, 2025 at 1:25 AM
Class A PBPs like PBP1 are not known to drive cell division in other bacteria. So we set out to determine how PBP1 evolved to take on this very important job. To begin to tackle this question, we used CRISPRi-compatible trans-complementation to conditionally express mutant variants of PBP1 in C diff
Excited to share my latest postdoctoral work in the Shen Lab at Tufts! In this study, we follow up on an exciting finding by former grad student @shailab.bsky.social that C diff uses its Class A PBP (PBP1) to drive cell division (unlike previously studied bacteria)! journals.plos.org/plosgenetics...
Molecular dissection of Class A PBP function uncovers novel features of the non-canonical Clostridioides difficile divisome complex
Author summary Bacterial cell division is an ancient and essential process, but our molecular understanding of this process is primarily based on studies in a select few model systems. Recent work fou...
journals.plos.org
October 28, 2025 at 1:25 AM
Excited to share my latest postdoctoral work in the Shen Lab at Tufts! In this study, we follow up on an exciting finding by former grad student @shailab.bsky.social that C diff uses its Class A PBP (PBP1) to drive cell division (unlike previously studied bacteria)! journals.plos.org/plosgenetics...
Reposted by Greg Harrison
Friendly reminder: 🎉 Pre-register today & get ready to join our FREE online celebration. Everyone is welcome. To keep #BlackInMicro alive Donate: tinyurl.com/GiveBiM and Register to attend: linktr.ee/BlackInMicro (see links in bio) #BiMWeek2025
October 3, 2025 at 8:40 PM
Friendly reminder: 🎉 Pre-register today & get ready to join our FREE online celebration. Everyone is welcome. To keep #BlackInMicro alive Donate: tinyurl.com/GiveBiM and Register to attend: linktr.ee/BlackInMicro (see links in bio) #BiMWeek2025
Reposted by Greg Harrison
UChicago Microbiology is searching for tenured or tenure-track faculty working in host-pathogens interactions, viral and bacterial pathogenesis, and emerging infectious diseases. Come join our vibrant Department! microbiology.uchicago.edu
Apply here apply.interfolio.com/174404
Apply here apply.interfolio.com/174404
Apply - Interfolio
{{$ctrl.$state.data.pageTitle}} - Apply - Interfolio
apply.interfolio.com
October 5, 2025 at 12:03 PM
UChicago Microbiology is searching for tenured or tenure-track faculty working in host-pathogens interactions, viral and bacterial pathogenesis, and emerging infectious diseases. Come join our vibrant Department! microbiology.uchicago.edu
Apply here apply.interfolio.com/174404
Apply here apply.interfolio.com/174404
Reposted by Greg Harrison
🚨 Microbiologists! We are recruiting Assistant / Associate Professors in 3 collaborative areas of our U. Pittsburgh School of Medicine.
1) MMG (my dept): fundamental research in med micro
2) Peds ID / I4Kids institute
3) Center for Vaccine Research
🔗 to all 3 w/info: www.linkedin.com/posts/vaughn...
1) MMG (my dept): fundamental research in med micro
2) Peds ID / I4Kids institute
3) Center for Vaccine Research
🔗 to all 3 w/info: www.linkedin.com/posts/vaughn...
Faculty Professor Associate - Full-Time | Vaughn Cooper
We are recruiting Faculty microbiologists in three (3) different, complementary, and collaborative areas at the University of Pittsburgh associated with the School of Medicine.
1) Fundamental researc...
www.linkedin.com
September 23, 2025 at 10:31 PM
🚨 Microbiologists! We are recruiting Assistant / Associate Professors in 3 collaborative areas of our U. Pittsburgh School of Medicine.
1) MMG (my dept): fundamental research in med micro
2) Peds ID / I4Kids institute
3) Center for Vaccine Research
🔗 to all 3 w/info: www.linkedin.com/posts/vaughn...
1) MMG (my dept): fundamental research in med micro
2) Peds ID / I4Kids institute
3) Center for Vaccine Research
🔗 to all 3 w/info: www.linkedin.com/posts/vaughn...
Fantastic meeting! Heard about SO MUCH groundbreaking work and met so many incredible people! Such a great community 😃
And that’s a wrap on the Great Wall Symposium 2025!
Roll on 2027, venue to be confirmed shortly …
Roll on 2027, venue to be confirmed shortly …
September 18, 2025 at 7:15 PM
Fantastic meeting! Heard about SO MUCH groundbreaking work and met so many incredible people! Such a great community 😃
Reposted by Greg Harrison
Rich Losick’s Farewell Publication Reexamines a Molecular Biology Milestone 🧪 🧬 #AcademicSky #higherEd
www.mcb.harvard.edu/department/n... @cryptogenomicon.bsky.social @craigphunter.bsky.social @rachellegaudet.bsky.social @harvardmagazine.bsky.social @naoshigeuchida.bsky.social
www.mcb.harvard.edu/department/n... @cryptogenomicon.bsky.social @craigphunter.bsky.social @rachellegaudet.bsky.social @harvardmagazine.bsky.social @naoshigeuchida.bsky.social
Rich Losick’s Farewell Publication Reexamines a Molecular Biology Milestone - Harvard University - Department of Molecular & Cellular Biology
Richard Losick, Maria Moors Cabot Professor of Biology, Emeritus in Harvard’s Department of Molecular and Cellular Biology, is about to publish what he describes as his “last paper”—though […]
www.mcb.harvard.edu
September 11, 2025 at 8:01 PM
Rich Losick’s Farewell Publication Reexamines a Molecular Biology Milestone 🧪 🧬 #AcademicSky #higherEd
www.mcb.harvard.edu/department/n... @cryptogenomicon.bsky.social @craigphunter.bsky.social @rachellegaudet.bsky.social @harvardmagazine.bsky.social @naoshigeuchida.bsky.social
www.mcb.harvard.edu/department/n... @cryptogenomicon.bsky.social @craigphunter.bsky.social @rachellegaudet.bsky.social @harvardmagazine.bsky.social @naoshigeuchida.bsky.social
Reposted by Greg Harrison
Analysis of essential genes in Clostridioides difficile by CRISPRi and Tn-seq | Journal of Bacteriology journals.asm.org/doi/10.1128/...
Analysis of essential genes in Clostridioides difficile by CRISPRi and Tn-seq | Journal of Bacteriology
Clostridioides difficile is an opportunistic pathogen for which better antibiotics are sorely needed. Most
antibiotics target pathways that are essential for viability. Here, we use saturation
transpo...
journals.asm.org
September 12, 2025 at 12:12 PM
Analysis of essential genes in Clostridioides difficile by CRISPRi and Tn-seq | Journal of Bacteriology journals.asm.org/doi/10.1128/...
Reposted by Greg Harrison
NEW: Don't ask too many questions, but...
NIH may not re-terminate the 900ish grants at issue in the main NIH lawsuits after all.
To the PIs of reinstated grants, SPEND NOW!
🧵 Here's what NIH is probably thinking. Bear with me:
NIH may not re-terminate the 900ish grants at issue in the main NIH lawsuits after all.
To the PIs of reinstated grants, SPEND NOW!
🧵 Here's what NIH is probably thinking. Bear with me:
August 29, 2025 at 2:50 PM
NEW: Don't ask too many questions, but...
NIH may not re-terminate the 900ish grants at issue in the main NIH lawsuits after all.
To the PIs of reinstated grants, SPEND NOW!
🧵 Here's what NIH is probably thinking. Bear with me:
NIH may not re-terminate the 900ish grants at issue in the main NIH lawsuits after all.
To the PIs of reinstated grants, SPEND NOW!
🧵 Here's what NIH is probably thinking. Bear with me: