Publications by authors named "Michael P Jennings"

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  • Tissue injury and ECM degradation are significant features of group A Streptococcus (GAS) skin infections, largely influenced by M proteins with lectin-like abilities.
  • The study found that M proteins from different GAS strains bind to hyaluronic acid through specific motifs, which affects keratinocyte wound healing negatively.
  • Understanding the interaction between hyaluronic acid and M proteins could help develop new nonantibiotic treatments to combat GAS skin infections by improving ECM composition and healing responses.
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  • Contact-dependent hemolysins are key virulence factors in certain human pathogens, like gonococci, with phospholipase A being a notable outer membrane protein that can lyse human red blood cells over three days.
  • Mutations in the phospholipase A gene significantly impair the bacteria's ability to survive in human immune cells, indicating its critical role in pathogenesis.
  • The inability of phospholipase A mutants to effectively lyse host cells underscores its importance for gonococcal survival and evasion of the host's immune response.
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Introduction: Gonorrhoea, the sexually transmissible infection caused by , has a substantial impact on sexual and reproductive health globally with an estimated 82 million new infections each year worldwide. antimicrobial resistance continues to escalate, and disease control is largely reliant on effective therapy as there is no proven effective gonococcal vaccine available. However, there is increasing evidence from observational cohort studies that the serogroup B meningococcal vaccine four-component meningitis B vaccine (4CMenB) (Bexsero), licensed to prevent invasive disease caused by , may provide cross-protection against the closely related bacterium .

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Plasmodium falciparum is a human-adapted apicomplexan parasite that causes the most dangerous form of malaria. P. falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion.

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biogroup is a human-adapted pathogen and the causative agent of Brazilian purpuric fever (BPF), an invasive disease with high mortality, that sporadically manifests in children previously suffering conjunctivitis. Phase variation is a rapid and reversible switching of gene expression found in many bacterial species, and typically associated with outer-membrane proteins. Phase variation of cytoplasmic DNA methyltransferases has been shown to play important roles in bacterial gene regulation and can act as epigenetic switches, regulating the expression of multiple genes as part of systems called phasevarions (phase-variable regulons).

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Non-typeable (NTHi) is a major bacterial pathogen of the human airway. We report high-depth coverage RNA-Seq data from prototype NTHi strains 723 and R2866, encoding two of the most common phase-variable ModA alleles found in NTHi strains, ModA2 and ModA10, respectively.

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  • In sub-Saharan Africa's meningitis belt, cyclic outbreaks of meningococcal disease are linked to specific hypervirulent strains that have shown significant genetic variation from 1998 to 2011.
  • Researchers conducted whole-genome sequencing on 100 isolates to explore genetic recombination in pilin glycosylation patterns, revealing that lateral gene transfer affects the glycosylation of cell surface proteins.
  • The study suggests variation in protein glycosylation allows these bacteria to adapt and evade immune responses, indicating potential targets for new vaccines and therapies.
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Many bacterial surface proteins and carbohydrates are modified with phosphorylcholine (ChoP), which contributes to host mimicry and can also promote colonization and survival in the host. However, the ChoP biosynthetic pathways that are used in bacterial species that express ChoP have not been systematically studied. For example, the well-studied Lic-1 pathway is absent in some ChoP-expressing bacteria, such as Neisseria meningitidis and Neisseria gonorrhoeae.

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Escherichia coli signal peptidase I (LepB) has been shown to inefficiently cleave secreted proteins with aromatic amino acids at the second position after the signal peptidase cleavage site (P2'). The Bacillus subtilis exported protein TasA contains a phenylalanine at P2', which in B. subtilis is cleaved by a dedicated archaeal-organism-like signal peptidase, SipW.

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Phosphorylcholine (ChoP) can be found in all life forms. Although this molecule was first thought to be uncommon in bacteria, it is now appreciated that many bacteria express ChoP on their surface. ChoP is usually attached to a glycan structure, but in some cases, it is added as a post-translational modification to proteins.

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Actinobacillus pleuropneumoniae is the cause of porcine pleuropneumonia, a severe respiratory tract infection that is responsible for major economic losses to the swine industry. Many host-adapted bacterial pathogens encode systems known as phasevarions (phase-variable regulons). Phasevarions result from variable expression of cytoplasmic DNA methyltransferases.

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One of the forms of aberrant glycosylation in human tumors is the expression of N-glycolylneuraminic acid (Neu5Gc). The only known enzyme to biosynthesize Neu5Gc in mammals, cytidine-5'-monophosphate-N-acetylneuraminic acid (CMAH), appears to be genetically inactivated in humans. Regardless, low levels of Neu5Gc have been detected in healthy humans.

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  • Neisseria gonorrhoeae has become resistant to all previous antibiotics, necessitating the search for new treatments.
  • Carbamazepine (Cz), an antiepileptic drug, has shown promise in blocking the infection process and clearing established gonorrheal infections in cervical cells.
  • In a study of 16 women, Cz was found in their vaginal fluid at levels high enough to significantly reduce viable gonococci, supporting Cz's potential as a targeted therapy for gonococcal cervicitis.
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Cutaneous melanoma is one of the most aggressive and deadly types of skin cancer and rates of disease are continuing to increase worldwide. Currently, no serum biomarkers exist for the early detection of cutaneous melanoma. Normal human cells cannot make the sialic acid sugar, Neu5Gc, yet human tumor cells express Neu5Gc and Neu5Gc-containing glycoconjugates have been proposed as tumor biomarkers.

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Adherence of nontypeable Haemophilus influenzae (NTHi) to the host airway is an essential initial step for asymptomatic colonization of the nasopharynx, as well as development of disease. NTHi relies on strict regulation of multiple adhesins for adherence to host substrates encountered in the airway. NTHi encode a phase-variable cytoplasmic DNA methyltransferase, ModA, that regulates expression of multiple genes; a phasevarion (phase-variable regulon).

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Multidrug-resistant (MDR) N. gonorrhoeae is a current public health threat. New therapies are urgently needed.

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Secreted proteins contain an N-terminal signal peptide to guide them through the secretion pathway. Once the protein is translocated, the signal peptide is removed by a signal peptidase, such as signal peptidase I. The signal peptide has been extensively studied and reviewed; however, the mature region has not been the focus of review.

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Extra-intestinal pathogenic Escherichia coli (ExPEC) belong to a critical priority group of antibiotic resistant pathogens. ExPEC establish gut reservoirs that seed infection of the urinary tract and bloodstream, but the mechanisms of gut colonisation remain to be properly understood. Ucl fimbriae are attachment organelles that facilitate ExPEC adherence.

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Streptococcus pneumoniae is the most common cause of bacterial illness worldwide. Current vaccines based on the polysaccharide capsule are only effective against a limited number of the >100 capsular serotypes. A universal vaccine based on conserved protein antigens requires a thorough understanding of gene expression in S.

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Background: Normal human tissues do not express glycans terminating with the sialic acid N-glycolylneuraminic acid (Neu5Gc), yet Neu5Gc-containing glycans have been consistently found in human tumor tissues, cells and secretions and have been proposed as a cancer biomarker. We engineered a Neu5Gc-specific lectin called SubB2M, and previously reported elevated Neu5Gc biomarkers in serum from ovarian cancer patients using a Surface Plasmon Resonance (SPR)-based assay. Here we report an optimized SubB2M SPR-based assay and use this new assay to analyse sera from breast cancer patients for Neu5Gc levels.

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-glycolylneuraminic acid (Neu5Gc), and its precursor -acetylneuraminic acid (Neu5Ac), commonly referred to as sialic acids, are two of the most common glycans found in mammals. Humans carry a mutation in the enzyme that converts Neu5Ac into Neu5Gc, and as such, expression of Neu5Ac can be thought of as a 'human specific' trait. Bacteria can utilize sialic acids as a carbon and energy source and have evolved multiple ways to take up sialic acids.

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  • Lav is a protein found in some pathogenic Haemophilus species, specifically non-typeable Haemophilus influenzae (NTHi), that can toggle between being active and inactive due to changes in a simple DNA sequence.
  • In studies of NTHi, the protein is mostly found in the inactive (OFF) state, but when expressed (ON), it enhances the bacteria's ability to adhere to human lung cells and form biofilms.
  • Genetic analysis shows that about 60% of NTHi strains carry the Lav gene, with five distinct variants identified across different Haemophilus species, suggesting that understanding Lav could provide insights into its role in various diseases.
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Polarized or precision targeting of protein complexes to their destinations is fundamental to cellular homeostasis, but the mechanism underpinning directional protein delivery is poorly understood. Here, we use the uropod targeting HIV synapse as a model system to show that the viral assembly machinery Gag is copolarized with the intracellular calcium (Ca) gradient and binds specifically with Ca. Conserved glutamic/aspartic acids flanking endosomal sorting complexes required for transport binding motifs are major Ca binding sites.

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Here, we present ultrastructural analyses showing that incoming HIV are captured near the lymphocyte surface in a virion-glycan-dependent manner. Biophysical analyses show that removal of either virion- or cell-associated N-glycans impairs virus-cell binding, and a similar glycan-dependent relationship is observed between purified HIV envelope (Env) and primary T cells. Trimming of N-glycans from either HIV or Env does not inhibit protein-protein interactions.

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  • HIV-1 may use the CR3 protein found on cervical epithelial cells to cross the mucosal barrier, which could be a key pathway for HIV infection in women.
  • The study demonstrates that HIV-1 shows a strong binding affinity to CR3 through specific regions of the protein, relying on certain glycans on the virus's surface for this interaction.
  • Blocking the CR3-HIV-1 interaction with antibodies or other compounds could potentially prevent the transmission of HIV across the cervical epithelium, suggesting new strategies for reducing the risk of infection in women.
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