molecular-evolution

Genomic comparison and phenotypic characterization of Pseudomonas aeruginosa isolates across environmental and diverse clinical isolation sites

Pseudomonas aeruginosa is a clinically significant, opportunistic pathogen adept at thriving in both host-associated and environmental settings. We sought to define the extent to which P. aeruginosa isolates specialize across niches using a …

Genotype-phenotype modeling of light ecotypes in Prochlorococcus reveals genomic signatures of ecotypic divergence

Prochlorococcus is a cyanobacterial genus that exhibits photosynthetic capacity and remarkable genetic diversity. We analyze how Prochlorococcus genomics relate to high vs. low light environment adaptations, applying traditional comparative genomics …

From sequence to signature: Uncovering multiscale AMR features across bacterial pathogens with supervised machine learning

Since the clinical introduction of antibiotics in the 1940s, antimicrobial resistance (AMR) has become an increasingly dire threat to global public health. Pathogens acquire AMR much faster than we discover new drugs (antibiotics), warranting …

The phage shock protein (PSP) envelope stress response: discovery of novel partners and evolutionary history

Bacterial phage shock protein (PSP) systems stabilize the bacterial cell membrane and protect against envelope stress. These systems have been associated with virulence, but despite their critical roles, PSP components are not well characterized …

The glutathione import system satisfies the Staphylococcus aureus nutrient sulfur requirement and promotes interspecies competition

Sulfur is an indispensable element for proliferation of bacterial pathogens. Prior studies indicated that the human pathogen, Staphylococcus aureus utilizes glutathione (GSH) as a source of nutrient sulfur; however, mechanisms of GSH acquisition are …

Phage defence by deaminase-mediated depletion of deoxynucleotides in bacteria

DciA Helicase Operators Exhibit Diversity across Bacterial Phyla

Despite the fundamental importance of DNA replication for life, this process remains understudied in bacteria outside Escherichia coli and Bacillus subtilis. In particular, most bacteria do not encode the helicase-loading proteins that are essential in E. coli and B. subtilis for DNA replication. Instead, most bacteria encode a DciA homolog that likely constitutes the predominant mechanism of helicase operation in bacteria. However, it is still unknown how DciA structure and function compare across diverse phyla that encode DciA proteins. In this study, we performed computational evolutionary analyses to uncover tremendous diversity among DciA homologs. These studies provide a significant advance in our understanding of an essential component of the bacterial DNA replication machinery.

Novel Internalin P homologs in Listeria ivanovii londoniensis and Listeria seeligeri

The intracellular bacterial pathogen Listeria monocytogenes can breach protective barriers in the pregnant host, allowing the colonization of the placenta in pregnant people and resulting in numerous adverse pregnancy outcomes. Previous studies aimed at delineating the mechanisms behind placental colonization of L. monocytogenes identified a key virulence factor, internalin P (InlP). The internalin family of proteins has been studied extensively due to their conservation in the genus Listeria and their contribution to virulence and pathogenicity in L. monocytogenes. Still, many questions remain regarding the evolution of internalins and their potential roles in non-pathogenic Listeria. Our work addresses this gap in knowledge by (1) identifying additional InlP homologs in Listeria, including L. ivanovii, L. seeligeri, L. innocua, and L. costaricensis, and (2) characterizing these homologs using computational evolutionary methods to compare their primary sequences, domain architectures, and structural models. Together, our findings contribute to the field by providing insights into the evolution of one key member of the internalin family, as well as serving as a catalyst for future studies of InlP and its role in Listeria pathogenesis.

Cross-database integration using evolution and machine learning to identify multiscale molecular building blocks for antibiotic resistance

MolEvolvR: a web-app for characterizing proteins using molecular evolution and phylogeny

Studying proteins through the lens of evolution can reveal features such as conserved domains, lineage-specific variants, and co-occurring domain architectures in phylogenetic context across all superkingdoms. MolEvolvR enables researchers to conduct …