Article
Microbiology
Vanessa Arato, Davide Oldrini, Luisa Massai, Gianmarco Gasperini, Francesca Necchi, Francesca Micoli
Summary: Shigellosis, caused by Shigella flexneri and S. sonnei, poses a major global health risk but lacks widely available vaccines. Understanding the immunogenicity of OAg is crucial for vaccine design. Research shows that different O-acetylation patterns do not significantly impact immune response, and shared epitopes do not induce cross-reactive antibodies.
Article
Biotechnology & Applied Microbiology
Huizhen Tian, Biaoxian Li, Tian Xu, Haolin Yu, Jingxuan Chen, Haiyan Yu, Shan Li, Lingbing Zeng, Xiaotian Huang, Qiong Liu
Summary: Shigellosis, caused by Shigella, poses a serious threat to health in many developing countries. Despite efforts to develop a vaccine, none has been proven effective. A new strategy combining the synthesis of Shigella O-antigen in Salmonella and using it as an antigen delivery platform shows promise for vaccine development against Shigella infection.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Immunology
Nicole Inge Richardson, Neil Ravenscroft, Vanessa Arato, Davide Oldrini, Francesca Micoli, Michelle M. Kuttel
Summary: Shigella, a pathogenic bacterium, is a major cause of diarrheal disease and death, especially impacting young children in low-income countries. Given the increasing antibiotic resistance in Shigella, there is a need for an effective vaccine targeting the bacterial lipopolysaccharide O-antigen. Research on S. flexneri serotype 6 suggests that O-acetylation may not be essential for the antigenicity of the serotype, as confirmed by an in vivo study in mice.
Article
Immunology
Vincenzo Torraca, Dominik Brokatzky, Sydney L. Miles, Charlotte E. Chong, P. Malaka De Silva, Stephen Baker, Claire Jenkins, Kathryn E. Holt, Kate S. Baker, Serge Mostowy
Summary: Shigella, including specific serotypes, can establish persistent infection in the zebrafish model. The O-antigen plays a crucial role in this process, and the serotype-associated effects observed in humans are also observed in zebrafish.
JOURNAL OF INFECTIOUS DISEASES
(2023)
Article
Microbiology
Mohammad Shahnaij, Mohammed Badrul Amin, M. Mozammel Hoque, Abdus Salam Mondol, Kazi Jewel Rana, Ishrat J. J. Azmi, Kaisar A. A. Talukder
Summary: Shigella flexneri serotype 6 is a prevalent serotype of shigellosis in Bangladesh. A novel subserotype, VI:E1037, was identified, which has a unique evolutionary ancestry. The subtyping of S. flexneri 6a and 6b strains from Bangladesh was performed using various methods, including biochemical properties, plasmid profiles, and DNA analysis, to support the classification of these subserotypes and highlight the need for global monitoring.
JOURNAL OF BACTERIOLOGY
(2023)
Article
Genetics & Heredity
Si -Nguyen T. Mai, Ladaporn Bodhidatta, Paul Turner, Sonam Wangchuk, Tuyen Ha Thanh, Phat Voong Vinh, Duy Thanh Pham, Maia A. Rabaa, Guy E. Thwaites, Nicholas R. Thomson, Stephen Baker, Hao Chung The
Summary: Shigella flexneri serotype 6, an understudied pathogen causing diarrhoeal diseases in developing countries, is phylogenetically distinct from other S. flexneri serotypes and more closely related to S. boydii. Population structure analysis revealed two phylogenetic groups in Asian S. flexneri serotype 6, originating in the 18th century and likely forming a dominant lineage in the 1970s. Genomic analyses showed widespread resistance to first-generation antimicrobials, with limited resistance to more recent options, and highlighted gene inactivation and loss events related to metabolism and cellular appendages, indicating reductive evolution in pathogen adaptation.
MICROBIAL GENOMICS
(2021)
Article
Biochemistry & Molecular Biology
Yang W. Huan, Jidapha Fa-arun, Baojun Wang
Summary: The alternative tail fiber S' of Enterobacteria phage P1 can efficiently transduce genes into Shigella flexneri and Escherichia coli bacteria. At least one O-antigen unit is required for P1(S') transduction. Improved transduction efficiency of P1(S') facilitates the delivery of antimicrobial genes into Shigella flexneri.
JOURNAL OF MOLECULAR BIOLOGY
(2022)
Article
Cell Biology
Munazza Rajput, Naresh K. Verma
Summary: Shigellosis is an acute gastrointestinal disease caused by the bacterium Shigella flexneri. Different serotypes of S. flexneri trigger serotype-specific immune responses. The recently identified O-acetyltransferase B (OacB) enzyme plays a role in modifying the O-antigen of S. flexneri.
BMC MOLECULAR AND CELL BIOLOGY
(2022)
Article
Infectious Diseases
Iqbal Nisa, Muhammad Qasim, Arnold Driessen, Jeroen Nijland, Fazal Adnan, Malik Nawaz Shuja, Hazir Rahman
Summary: This study investigated the distribution of virulence factors among different serotypes of S. flexneri in Pakistan, revealing that serotype 2b is the most virulent strain with a complete set of five virulence genes, which is associated with high disease severity.
INFECTION GENETICS AND EVOLUTION
(2021)
Article
Medicine, General & Internal
Karrie K. K. Ko, Joash Jun Keat Chu, Kar Mun Lim, Hatairat Yingtaweesittikul, Wenjie Huang, Shireen Yan Ling Tan, Kenneth Choon Meng Goh, Si Huei Tan, Tong Yong Ng, Matthias Maiwald, Jonathan Wei Zhong Chia, Delphine Yanhong Cao, Yen Ee Tan, James Heng Chiak Sim, Tse Hsien Koh, Niranjan Nagarajan, Chayaporn Suphavilai
Summary: This study reports the detection of a clonal cluster of multidrug-resistant S. flexneri in Singapore, characterized by whole-genome sequence analysis and phenotypic testing. The study also demonstrates that near real-time sentinel-site sequence-based surveillance can timely detect possible clonal outbreak clusters and provide alerts useful for public health mitigations.
FRONTIERS IN MEDICINE
(2022)
Article
Biochemistry & Molecular Biology
Maria Michelina Raso, Oscar Vassallo, Francesca Micoli, Carlo Giannelli
Summary: Shigella is a leading cause of diarrheal disease worldwide, particularly in low- and middle-income countries and young children. Vaccine development targeting S. flexneri serotype 6 O-antigen is a high priority due to increasing levels of antimicrobial resistance. Two optimized methods for quantifying S. flexneri 6 O-antigen have been developed, with one allowing for increased sensitivity and the other providing more specific detection. These methods will aid in the characterization of vaccines targeting S. flexneri 6 O-antigen.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Immunology
Ahmed Gaballa, Martin Wiedmann, Laura. M. M. Carroll
Summary: Phosphoethanolamine transferases (PET) are closely related to colistin resistance genes (mcr) and can confer resistance to the last-resort antimicrobial colistin. Through studying the sequence similarity and evolution patterns of mcr and PET, we identified 125 putative novel mcr-like genes that share similar evolutionary patterns with i-PET genes. Our findings suggest that PET genes can give rise to colistin resistance genes through various mechanisms, including mobilization, selection, and diversification of genomic context and regulatory pathways. These mechanisms likely altered gene expression levels and enzyme activity, allowing bona fide PET genes to evolve to function in colistin resistance.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2023)
Article
Microbiology
Min Yan Teh, Elizabeth Ngoc Hoa Tran, Renato Morona
Summary: The study aimed to expand the host range of Sf6 to the prevalent S. flexneri serotype 2a(2) strain. A new lytic Sf6 host range mutant was discovered, which is capable of infecting S. flexneri serotype 2a(2). Residues in Sf6TSP that may potentially be involved in binding and hydrolysing serotype 2a LPS Oag were also identified. This work increased the limited Shigella-specific bacteriophage collection and may be useful for future phage therapy and/or biocontrolling of S. flexneri in contaminated food and water.
FEMS MICROBIOLOGY LETTERS
(2022)
Article
Microbiology
Alice Ascari, Elizabeth Ngoc Hoa Tran, Bart A. Eijkelkamp, Renato Morona
Summary: This study investigates the specific binding interactions between the polymerase Wzy(SF) and its copolymerase counterparts in Shigella flexneri. It identifies a unique binding site for Wzz(pHS-2) on Wzy(SF) and elucidates key moieties that regulate this interaction. This novel understanding of the molecular interaction in the biosynthesis pathway provides insights into polysaccharide synthesis in Gram-negative bacteria.
JOURNAL OF BACTERIOLOGY
(2022)
Article
Biotechnology & Applied Microbiology
Siqi Li, Xinfeng Han, Ipshita Upadhyay, Weiping Zhang
Summary: This study identified functional epitopes of IpaB protein, particularly from the N terminus, and proposed using them for the development of a cross-protective Shigella vaccine. Three identified epitopes showed potential for inducing protective antibodies against Shigella invasion, indicating their usefulness in vaccine development.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)