Genomic features and pathogenic potential of <em>Streptococcus agalactiae</em> isolated from bovine clinical mastitis
J Adv Vet Anim Res. 2025 Mar 24;12(1):80-89. doi: 10.5455/javar.2025.l874. eCollection 2025 Mar.
ABSTRACT
OBJECTIVE: The goal of this study is to describe the genome of Streptococcus agalactiae that was found in clinical mastitis in cattle in Bangladesh. This work will show how strong the bacteria are and how important they are for public health.
MATERIALS AND METHODS: Whole genome sequencing (WGS) was performed using the Illumina MiSeq platform, followed by comprehensive analysis with various bioinformatic tools to identify key genomic features.
RESULTS: WGS revealed that the isolates are closely related, belonging to sequence type ST4, a rare type previously identified in both human and animal hosts. The isolates possess 44 virulence-related genes linked to adherence, capsule biogenesis, enzyme production, immunoreactive antigens, protease, and cytolysin production. They also carry two pilus islands (PIs), PI-1 and PI-2b, which are often associated with invasive diseases. PI-2b proteins are key targets for vaccine development against Group B Streptococcus (GBS). The isolates belong to serotype Ia and carry the gbs2018-2 variant, indicating their adaptability to a wide range of hosts, including humans and animals. These virulence factors are critical for understanding S. agalactiae's pathogenicity and developing vaccines against its infections. Additionally, the isolates harbor antimicrobial resistance genes conferring resistance to glycopeptides (vanT, vanY), macrolides (mreA), peptides (mprF), penicillins and β-lactams (pbp), and aminoglycosides. Source tracking via the BacWGSTdb website identified these isolates as closely related to human pathogens, indicating their zoonotic potential.
CONCLUSION: These results suggest that S. agalactiae could be a zoonotic pathogen. This highlights the need for ongoing genomic surveillance to fully understand how it causes disease and come up with effective ways to control it.
PMID:40568491 | PMC:PMC12186781 | DOI:10.5455/javar.2025.l874
Amyloid Forming Human Lysozyme Intermediates are Stabilized by Non-Native Amide-π Interactions
Adv Sci (Weinh). 2025 Jun 25:e03957. doi: 10.1002/advs.202503957. Online ahead of print.
ABSTRACT
Mutational variants of human lysozyme cause a rare but fatal hereditary systemic amyloidosis by populating an intermediate state that self-assembles into amyloid fibrils. However, this intermediate state is recalcitrant to detailed structural investigation, as it is only transiently and sparsely populated. Here, this work investigates the intermediate state of an amyloid-forming human lysozyme variant (I59T) using CEST and CPMG RD NMR at low pH. 15N CEST profiles probe the thermal unfolding of the native state into the denatured ensemble and reveal a distinct intermediate state. Global fitting of 15N CEST and CPMG data provides kinetic and thermodynamic parameters, characterizing the intermediate state populated at 0.6%. 1H CEST data further confirm the presence of the intermediate state displaying unusually high or low 1HN chemical shifts. To investigate the structural details of this intermediate state, this work uses molecular dynamics (MD) simulations, which recapitulate the experimentally observed folding pathway and free energy landscape. This work observes a high-energy intermediate state with a locally disordered β-domain and C-helix, stabilized by non-native hydrogen bonding and amide-π interactions, accounting for its anomalous 1H chemical shifts. Together, these NMR and MD data provide the first direct structural information on the intermediate state, offering insights into targeting lysozyme amyloidosis.
PMID:40557600 | DOI:10.1002/advs.202503957
Amyloid Forming Human Lysozyme Intermediates are Stabilized by Non-Native Amide-π Interactions
Adv Sci (Weinh). 2025 Jun 25:e03957. doi: 10.1002/advs.202503957. Online ahead of print.
ABSTRACT
Mutational variants of human lysozyme cause a rare but fatal hereditary systemic amyloidosis by populating an intermediate state that self-assembles into amyloid fibrils. However, this intermediate state is recalcitrant to detailed structural investigation, as it is only transiently and sparsely populated. Here, this work investigates the intermediate state of an amyloid-forming human lysozyme variant (I59T) using CEST and CPMG RD NMR at low pH. 15N CEST profiles probe the thermal unfolding of the native state into the denatured ensemble and reveal a distinct intermediate state. Global fitting of 15N CEST and CPMG data provides kinetic and thermodynamic parameters, characterizing the intermediate state populated at 0.6%. 1H CEST data further confirm the presence of the intermediate state displaying unusually high or low 1HN chemical shifts. To investigate the structural details of this intermediate state, this work uses molecular dynamics (MD) simulations, which recapitulate the experimentally observed folding pathway and free energy landscape. This work observes a high-energy intermediate state with a locally disordered β-domain and C-helix, stabilized by non-native hydrogen bonding and amide-π interactions, accounting for its anomalous 1H chemical shifts. Together, these NMR and MD data provide the first direct structural information on the intermediate state, offering insights into targeting lysozyme amyloidosis.
PMID:40557600 | DOI:10.1002/advs.202503957
Association of LEPR Gene Polymorphisms With Youth-Onset Diabetes in Bangladesh
Cureus. 2025 May 23;17(5):e84696. doi: 10.7759/cureus.84696. eCollection 2025 May.
ABSTRACT
Introduction Polymorphisms of the leptin receptor (LEPR) gene are associated with type 2 diabetes mellitus (T2DM), but the association varies among different geographic populations. The present study aims to observe the association of single-nucleotide polymorphisms (SNPs) of the LEPR gene (rs1137100 and rs1137101) with youth-onset T2DM in Bangladesh. Methods This case-control study encompassed 62 individuals with youth-onset T2DM (age range 18-29 years) and an equal number of age-matched controls with normal glucose tolerance (NGT). Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Genotypes of both LEPR SNPs were expressed as AA, AG, and GG, where G is considered a risk allele. Results The frequency of G-allele was higher in DM than in NGT for both rs1137100 (55.6% (69/124) vs. 42.7% (53/124); OR 1.7, 95% CI 1.02-2.78; p=0.042) and rs1137101 (59.7% (74/124) vs. 41.9% (52/124); OR 95% CI 1.24-3.40, p=0.005). In the codominant model, the GG genotype was associated with DM (GG vs. AA: rs1137100: OR 3.37; CI 1.11-10.19; p=0.032; rs1137101: OR 4.93; CI 1.62-14.99; p=0.005) but not the AG genotype (AG vs. AA). In the dominant model, the risk variants AG+GG (vs. AA) of rs1137100 did not have an association (p=0.289), but rs1137101 had (OR 2.60; CI 1.07-6.33; p=0.035). In the recessive model, risk variant GG (vs. AG+AA) of both SNPs had an association with DM (rs1137100: OR 2.98; CI 1.19-7.47; p=0.017; rs1137101: OR 3.02; CI 1.25-7.27; p=0.014). No association was significant in any models when adjusted for body mass index (BMI). Conclusion Although the LEPR gene SNPs rs1137100 and rs1137101 show a potential association with an increased risk of youth-onset T2DM in the Bangladeshi population, this association appears to be BMI-dependent.
PMID:40551902 | PMC:PMC12182985 | DOI:10.7759/cureus.84696