The toxin-coregulated pilus (TCP) is a critical determinant of the pathogenicity of Vibrio cholerae. This bundle-forming pilus is an essential intestinal colonization factor and also serves as a receptor for CTXphi, the filamentous phage that encodes cholera toxin (CT). TCP is a polymer of repeating subunits of the major pilin protein TcpA and tcpA is found within the Vibrio pathogenicity island (VPI). In this study genetic variation at the tcpA locus in toxigenic isolates of V. cholerae was investigated and three novel TcpA sequences from V. cholerae strains V46, V52 and V54, belonging to serogroups O141, O37 and O8, respectively, were identified. These novel tcpA alleles grouped into three distinct clonal lineages. The polymorphisms in TcpA were predominantly located in the carboxyl region of TcpA in surface-exposed regions of TCP fibres. Comparison of the genetic diversity among V. cholerae isolates at the tcpA locus with that of aldA, another locus within the VPI, and mdh, a chromosomal locus, revealed that tcpA sequences are far more diverse than these other loci. Most likely, this diversity is a reflection of diversifying selection in adaptation to the host immune response or to CTXphi susceptibility. An assessment of the functional properties of the variant tcpA sequences in the non-O1 V. cholerae strains was carried out by analysing whether these strains could be infected by CTXphi and colonize the suckling mouse. Similar to El Tor strains of V. cholerae O1, in vitro CTXphi infection of these strains required the exogenous expression of toxT, suggesting that in these strains ToxT regulates TCP expression and that these TcpA variants can serve as CTXphi receptors. All the V. cholerae non-O1 serogroup isolates tested were capable of colonizing the suckling mouse small intestine, suggesting that the different TcpA variants could function as colonization factors.
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http://dx.doi.org/10.1099/00221287-148-6-1655 | DOI Listing |
Front Immunol
January 2025
Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
Background: The Arp2/3 complex is a key regulator of tumor metastasis, and targeting its subunits offers potential for anti-metastatic therapy. However, the expression profiles, prognostic relevance, and diagnostic value of its subunits across cancers remain poorly understood. This study aims to investigate the clinical relevance of Arp2/3 complex subunits, particularly ARPC1A, in pan-cancer, and to further analyze the potential biological mechanisms of ARPC1A, as well as its association with immune infiltration and chemotherapy drug sensitivity.
View Article and Find Full Text PDFSensors (Basel)
January 2025
School of Information Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Spectrum sensing is recognized as a viable strategy to alleviate the scarcity of spectrum resources and to optimize their usage. In this paper, considering the time-varying characteristics and the dependence on various timescales within a time series of samples composed of in-phase (I) and quadrature (Q) component signals, we propose a multi-scale time-correlated perceptual attention model named MSTC-PANet. The model consists of multiple parallel temporal correlation perceptual attention (TCPA) modules, enabling us to extract features at different timescales and identify dependencies among features across various timescales.
View Article and Find Full Text PDFDiscov Oncol
November 2024
Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230001, Anhui, China.
Background: GNL2, a nuclear protein, is involved in ribosome production and cell cycle regulation. However, its expression and function in different types of tumors are not well understood. Comprehensive studies across multiple cancer types are needed to assess the potential of GNL2 as a diagnostic, prognostic, and immunological marker.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2025
Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China. Electronic address:
Based on the mixed ligand strategy, two new isostructural Cd coordination polymers: {[Cd(tcpa)(bima)(DMF)]‧3DMF} (CP 1), {[Cd(tcpa)(bmima)(DMF)]‧3DMF} (CP 2) were synthesized by combining two flexible anthracene-based and a triphenylamine-based ligands with large π-electron-rich structure using a solvothermal method (Htcpa = tris(4-carboxyphenyl)amine; bima = 9,10-bis(1H-imidazole-1-yl)methyl)anthracene and bmima = 9,10-bis((2-methyl-1H-imidazol-1-yl)methyl)anthracene). CP 1 and CP 2 show an unreported new 3D (3,14)-c net structure with the {4·6·8}{4} topology. Both CPs could detect CrO, Nitroaromatic explosives 2,4,6-Trinitrophenol (TNP) and 2,4-dinitrophenol (DNP) through rapid fluorescence quenching response with high quenching efficiency Ksv and low LOD with 0.
View Article and Find Full Text PDFHealth Informatics J
October 2024
Institute of Medical Information, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
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