About

Mechthild Pohlschroder is a faculty member in the Biomedical Graduate Studies at the Perelman School of Medicine at the University of Pennsylvania. Her research focuses on prokaryotic cell surface biogenesis and function, particularly in archaea and bacteria. Using the model archaeon Haloferax volcanii, her lab employs molecular biology, biochemistry, microscopy, RNAseq, and other cutting-edge technologies to characterize archaeal cell surface biology, including cell envelope functions, surface structures, and protein transport mechanisms. Her work has advanced the understanding of conserved pathways such as the Sec and Tat pathways, and uncovered unique archaeal surface anchoring strategies and membrane mechanisms conserved between archaea and bacteria. Her research also explores the roles of archaeal surface filaments and type IV pilins in biofilm formation and cell motility. She has contributed to the development of software programs to predict substrates involved in transport and cell surface anchoring pathways. Her lab's studies have provided insights into archaeal surface biology, protein secretion, and the molecular mechanisms underlying cell stability, motility, and adherence in prokaryotes.

Research topics

• Biology
• Cell biology
• Computational biology
• Biochemistry
• Genetics

Selected publications

• Characterization of aliA and aliB deletion mutants reveals a dominant role of AliA in Haloferax volcanii lipoprotein lipidation

  Zenodo (CERN European Organization for Nuclear Research) · 2026-01-01

  datasetOpen accessSenior author

  This dataset includes the custom Python pipelines used for proteomics data filtering and figure generation, as well as raw and processed qPCR data, accompanying the manuscript submission "Characterization of aliA and aliB deletion mutants reveals a dominant role of AliA in Haloferax volcanii lipoprotein lipidation". This dataset can be used to reproduce the results described in the manuscript.

  PublisherDOI

• Characterization of aliA and aliB deletion mutants reveals a dominant role of AliA in Haloferax volcanii lipoprotein lipidation

  Open MIND · 2026-01-01

  datasetSenior author

  This dataset includes the custom Python pipelines used for proteomics data filtering and figure generation, as well as raw and processed qPCR data, accompanying the manuscript submission "Characterization of aliA and aliB deletion mutants reveals a dominant role of AliA in Haloferax volcanii lipoprotein lipidation". This dataset can be used to reproduce the results described in the manuscript.

  DOI

• Beyond Access: A Holistic Model for STEM Leadership Development Integrating Early Research, Mentorship, and Community Partnership  

  Research Square · 2026-03-13

  preprintOpen accessSenior author
  PublisherOA PDFDOI

• Raw LC-MS Data for "AliA and AliB exhibit distinct enzymatic activities in lipoprotein lipidation in the model archaeon Haloferax volcanii"

  Open MIND · 2026-02-16

  datasetSenior author

  Raw LC-MS data for the paper "AliA and AliB exhibit distinct enzymatic activities in lipoprotein lipidation in the model archaeon Haloferax volcanii". Includes both core lipid data and methyl-iodide treated lipoprotein extract data for the YH_57 (∆aliB) and YH_113 (∆aliA) strains. Data for the parental strain (H53) and double deletion strain (∆aliA∆aliB) are provided in a separate deposit: https://doi.org/10.25740/vq241jx8767.

  DOI

• Characterization of <i>aliA</i> and <i>aliB</i> deletion mutants reveals a dominant role of AliA in <i>Haloferax volcanii</i> lipoprotein lipidation

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-03-11

  articleOpen accessSenior authorCorresponding

  ABSTRACT Protein lipidation is a widespread strategy for anchoring proteins to cellular membranes across all domains of life, yet the mechanisms underlying this process in archaea remain poorly understood. Recently, the first archaeal enzymes involved in lipobox-containing protein (lipoprotein) biogenesis, AliA and AliB, were identified and characterized in the model archaeon Haloferax volcanii . Although these paralogs share significant sequence similarity, distinct deletion phenotypes suggest differences in their substrate specificity and function. Here, we employed large-scale Triton X-114 fractionation followed by quantitative proteomics and lipid-specific mass spectrometry to systematically analyze AliA- and AliB-dependent lipoprotein lipidation. Deletion of aliA affected substantially more lipoproteins in Hfx. volcanii than deletion of aliB , markedly diminishing their TX-114 enrichment—indicating reduced hydrophobicity—and abolishing thioether-linked archaeol modification. This establishes AliA as the primary enzyme responsible for archaeal lipoprotein lipidation. In contrast, deletion of aliB affected only a small subset of lipoproteins and did not significantly reduce thioether-linked archaeol levels. In addition to defining distinct and non-redundant roles for AliA and AliB, this study provides the first large-scale experimental validation of predicted archaeal lipoproteins and identifies candidate components of the archaeal lipoprotein biogenesis pathway, substantially advancing mechanistic understanding and enabling improved lipoprotein prediction in this previously underexplored field.

  PublisherOA PDFDOI

• Supplemental Data for "Revisiting protein glycosylation in Pseudomonas aeruginosa reveals distinct phenotypes in motility and biofilm formation for different O-glycosylation pathway mutants"

  Zenodo (CERN European Organization for Nuclear Research) · 2026-01-10

  datasetOpen access

  This dataset contains the following supplemental data associated with the manuscript "Revisiting protein glycosylation in Pseudomonas aeruginosa reveals distinct phenotypes in motility and biofilm formation for different O-glycosylation pathway mutants": whole genome sequencing data of fgtA (CW1, CW2) and wbpL (CW5, CW8) deletion mutants CLSM imaging data of all analyzed strains

  PublisherDOI

• Accompanying data for "A Two-Component Regulatory System Mediates Quorum Sensing–Dependent Morphology and Motility Transitions in the Archaeon Haloferax volcanii"

  Zenodo (CERN European Organization for Nuclear Research) · 2026-04-22

  datasetOpen accessSenior author

  This repository contains materials to accompany the manuscript “A Two-Component Regulatory System Mediates Quorum Sensing–Dependent Morphology and Motility Transitions in the Archaeon Haloferax volcanii” and can be used to reproduce the results described in the study.

  PublisherDOI

• Supplemental Data for "Revisiting protein glycosylation in Pseudomonas aeruginosa reveals distinct phenotypes in motility and biofilm formation for different O-glycosylation pathway mutants"

  Zenodo (CERN European Organization for Nuclear Research) · 2026-01-10

  datasetOpen access

  This dataset contains the following supplemental data associated with the manuscript "Revisiting protein glycosylation in Pseudomonas aeruginosa reveals distinct phenotypes in motility and biofilm formation for different O-glycosylation pathway mutants": whole genome sequencing data of fgtA (CW1, CW2) and wbpL (CW5, CW8) deletion mutants CLSM imaging data of all analyzed strains

  PublisherDOI

• Abstract 2725 The Chemistry of Community

  Journal of Biological Chemistry · 2025-05-01

  articleOpen access1st authorCorresponding

  A culturally aware scientific workforce is essential to addressing critical global challenges such as public health crises and climate change, while also rebuilding trust with marginalized communities. Mentorship that builds connections through shared passion is key to developing such a workforce in the realm of STEM. By doing so, we incorporate multiple cultural and intellectual perspectives to prepare the next generation of scientists for real world application of STEM beyond a sterile lab. Penn's First Exposure to Research in the Biological Sciences (PennFERBS) program, recruits high-achieving undergraduate students and immerses them in cutting-edge research and community partnership initiatives, highlighting the invaluable contributions of diverse scientists in STEM.

  PublisherOA PDFDOI

• Quorum sensing mediates morphology and motility transitions in the model archaeon <i>Haloferax volcanii</i>

  mBio · 2025-06-18 · 5 citations

  articleOpen accessSenior author

  ABSTRACT Quorum sensing (QS) is a population density-dependent mechanism of intercellular communication, whereby microbes secrete and detect signals to regulate behaviors such as virulence and biofilm formation. Although QS is well-studied in bacteria, little is known about cell-cell communication in archaea. The model archaeon Haloferax volcanii can transition from motile rod-shaped cells to non-motile disks as population density increases. In this report, we demonstrate that this transition is induced by a secreted small molecule present in cell-free conditioned medium (CM). The CM also elicits a response from a bacterial QS bioreporter, suggesting the potential for inter-domain crosstalk. To investigate the Hfx. volcanii QS response, we performed quantitative proteomics and detected significant differential abundances of 236 proteins in the presence of CM, including proteins involved in cell structure, motility, glycosylation, and two-component systems. We also demonstrate that a mutant lacking the cell shape regulatory factor DdfA does not undergo shape and motility transitions in the presence of CM, allowing us to identify protein abundance changes in the QS response pathway separate from those involved in shape and motility. In the ∆ ddfA strain, only 110 proteins had significant differential abundance, and comparative analysis of these two proteomics experiments enabled us to identify proteins dependent on and independent of DdfA in the QS response pathway. Our study provides the first detailed analysis of QS pathways in any archaeon, strengthening our understanding of archaeal communication as well as providing the framework for studying intra- and interdomain crosstalk. IMPORTANCE Understanding the complex signaling networks in microbial communities has led to many invaluable applications in medicine and industry. Yet, while archaea are ubiquitous and play key roles in nutrient cycling, little is known about the roles of archaeal intra- and interspecies cell-cell communication in environments such as the human, soil, and marine microbiomes. In this study, we established the first robust system for studying quorum sensing in archaea by using the model archaeon Haloferax volcanii . We demonstrated that different behaviors, such as cell shape and motility, are mediated by a signal molecule, and we uncovered key regulatory components of the signaling pathway. This work advances our understanding of microbial communication, shedding light on archaeal intra- and interdomain interactions, and contributes to a more complete picture of the interconnected networks of life on Earth.

  PublisherDOI

Recent grants

• Deciphering the roles of differential type IV pilin expression and N-glycosylation in biofilm formation

  NSF · $946k · 2018–2022

• Archaeal Sec-Dependent Protein Translocation

  NSF · $343k · 2003–2007

• Archaeal Sec-Dependent Protein Translocation

  NSF · $456k · 2007–2012

• Elucidating the mechanisms of morphological plasticity in archaea

  NSF · $1.2M · 2022–2026

• A Novel Anchoring Mechanism for Prokaryotic Surface Proteins

  NSF · $742k · 2014–2018

Frequent coauthors

• Stefan Schulze

  Rochester Institute of Technology

  33 shared

• Wailap Victor Ng

  National Yang Ming Chiao Tung University

  24 shared

• Leroy Hood

  Institute for Systems Biology

  24 shared

• Stephen R. Lasky

  24 shared

• Gregory G. Mahairas

  24 shared

• Min Pan

  Guangzhou Medical University

  24 shared

• Vésteinn Thórsson

  24 shared

• Young Ah Goo

  James S. McDonnell Foundation

  24 shared

Labs

• Pohlschroder LabPI