Article
Immunology
Weiwen Wang, Dongxing Tian, Dakang Hu, Wenjie Chen, Ying Zhou, Xiaofei Jiang
Summary: This study focused on the impact of rmpA and wcaJ on capsule synthesis. The results showed that rmpA could promote the production of hypercapsules by simultaneously acting on three promoters in the cps gene cluster, while wcaJ loss led to the termination of capsule synthesis. Furthermore, unlike rmpA, the sequence consistency of wcaJ was limited to the same bacterial group, causing wcaJ to function with sequence recognition specificity in different bacterial groups.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2023)
Article
Infectious Diseases
Xuejiao Ma, Li Zhang, Chengcheng Yue, YanYan Liu, Jiabin Li
Summary: The experiment showed that sub-Minimal Inhibitory Concentrations (sub-MIC) of levofloxacin (LVX) can reduce the mucoviscosity and CPS production of hypervirulent Klebsiella pneumoniae (hvKp). The down-regulation of virulence genes by LVX led to increased susceptibility to phagocytosis by macrophages, as demonstrated in mouse lethality assay. LVX may serve as a potential anti-virulence agent for refractory infections by hvKp.
INFECTION AND DRUG RESISTANCE
(2022)
Article
Microbiology
Md Roushan Ali, Yu Yang, Yuanyuan Dai, Huaiwei Lu, Zhien He, Yujie Li, Baolin Sun
Summary: This study conducted molecular and phenotypic analysis on multidrug-resistant hypervirulent K. pneumoniae (MDR-hvKp), revealing two isolates lacking mucoid regulators and virulence factors. The genetic and phenotypic features of these isolates were described, providing important insights into the identification of MDR-hvKp isolates.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Microbiology
Miran Tang, Zeyu Huang, Xiaodong Zhang, Jingchun Kong, Beibei Zhou, Yijia Han, Yi Zhang, Lijiang Chen, Tieli Zhou
Summary: In this study, it was found that there is still room for optimization in phage therapy for hypervirulent Klebsiella pneumoniae infection. The use of phages can decrease the virulence and fitness of the bacteria and the newly isolated phages have broader killing capabilities against phage-resistant mutants.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Microbiology
Robert E. Gertz, Fabiana C. Pimenta, Sopio Chochua, Shanda Larson, Anne-Kathryn Venero, Godfrey Bigogo, Jennifer Milucky, Maria da Gloria Carvalho, Bernard Beall
Summary: This study highlights the presence of nonpneumococcal strains carrying genes similar to those of pneumococcal capsular serotypes, potentially affecting population immunity to circulating pneumococcal strains. The overlapping serotypes between nonpathogenic commensal species and Streptococcus pneumoniae may have implications for pneumococcal epidemiology and vaccine strategies. The discovery of nonpneumococcal strains expressing serotypes identical to those targeted by pneumococcal conjugate vaccines expands our understanding of the distribution and potential impact of these strains.
Article
Chemistry, Organic
Diksha Rai, Suvarn S. Kulkarni
Summary: In this study, we successfully synthesized the tetrasaccharide repeating units of Acinetobacter baumannii strain 34 and O5, which have a common disaccharide motif [alpha-l-FucpNAc-(1 -> 4)-alpha-d-GalpNAcA], using a 2-azido-d-galacturonic acid derivative as the donor for the installation of 1,2-cis linkages. The total synthesis was achieved through relatively long linear sequences of 19 and 21 steps, with overall yields of 9.8% and 8.4%, respectively.
Article
Infectious Diseases
A. M. Parrott, J. Shi, J. Aaron, D. A. Green, S. Whittier, F. Wu
Summary: Multiple strains of hypervirulent Klebsiella pneumoniae (hvKp) are emerging in New York City, associated with higher mortality compared to multidrug-resistant and classical Klebsiella infections. Co-existing hepatobiliary disease appears to be a potential risk factor for these infections.
CLINICAL MICROBIOLOGY AND INFECTION
(2021)
Article
Chemistry, Organic
Jiaming Ao, Xiaoya Zhao, Siai Zhou, Yajing Guo, Guoqing Wang, Sixian Fang, Xuewen Yao, Yuhua Liu, Akihiro Ishiwata, Katsunori Tanaka, Feiqing Ding, Hui Cai
Summary: The core repeating tetrasaccharide unit of the prevalent Streptococcus pneumoniae 23F capsule polysaccharide was synthetized through a stereocontrolled reaction mediated by a zinc cation. The successful synthesis was achieved by using a specific reaction pathway and the directing effect of the metal ion.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Microbiology
Chao Yan, Yao Zhou, Shuheng Du, Bing Du, Hanqing Zhao, Yanling Feng, Guanhua Xue, Jinghua Cui, Lin Gan, Junxia Feng, Zheng Fan, Tongtong Fu, Ziying Xu, Qun Zhang, Rui Zhang, Xiaohu Cui, Ziyan Tian, Yujie Chen, Ting Zhang, Lei Huang, Jing Yuan
Summary: In this study, a recombinase-aided amplification (RAA) method targeting hvKp genes peg344 and rmpA was developed for the rapid and sensitive detection of hvKp. The assay showed high sensitivity, specificity, and clinical applicability, and was able to accurately detect hvKp in 208 clinical samples.
MICROBIOLOGY SPECTRUM
(2023)
Review
Medical Laboratory Technology
Piaopiao Dai, Dakang Hu
Summary: This article extensively discusses the virulence and carbapenem-resistance of Klebsiella pneumoniae, as well as their convergence. High-virulence strains of K. pneumoniae, including hypervirulent carbapenem-resistant strains, have become a global concern due to their extreme drug resistance and virulence.
JOURNAL OF CLINICAL LABORATORY ANALYSIS
(2022)
Article
Multidisciplinary Sciences
Aarti Pustam, Jayaraj Jayaraman, Adesh Ramsubhag
Summary: This study characterized the whole genomes of clinical K. pneumoniae and K. quasipneumoniae isolates from Trinidad, West Indies using Illumina sequencing. The analysis revealed significant virulence biomarkers and mobile elements associated with these isolates. The diversity of Trinidadian clinical K. pneumoniae isolates and the genomic data obtained can be used for future surveillance and genomic studies in this country and the wider Caribbean region.
Article
Infectious Diseases
Xiaolong Ma, Xiaodong Lv, Sihan Feng, Ruishan Liu, Hao Fu, Feng Gao, Hao Xu
Summary: This study presents a clinical hypervirulent Klebsiella pneumoniae isolate co-producing MCR-1, NDM-1, and OXA-10 causing bacteremia, highlighting the urgent need for infection control of such strains to prevent extensive-drug resistant clones.
INFECTION AND DRUG RESISTANCE
(2022)
Article
Chemistry, Organic
Antara Ghosh, Suvarn S. Kulkarni
Summary: In this study, the total synthesis of a linear, conjugation-ready, tetrasaccharide repeating unit of Vibrio vulnificus MO6-24 was reported. The synthesis involved rare amino sugars and consecutive glycosidic linkages, and was completed in 29 steps with an overall yield of 0.7% starting from l-rhamnose.
Article
Microbiology
Fan Zhang, Claudette Thompson, Nicole Ma, Ying-Jie Lu, Richard Malley
Summary: Capsular polysaccharides (CPSs) are important antigenic targets against bacterial infections. However, they elicit short-lived immune responses and are poorly immunogenic in young children. Coupling CPS with protein carriers enhances anti-CPS responses and generates long-lasting immune memory. This study aims to dissect the different mechanisms whereby carrier proteins enhance anti-CPS immunity, including modifying CPS interaction with antigen-presenting cells, activating CPS-specific B cells via interaction with T helper cells, and potentiating the recall of anti-CPS responses by engaging memory T helper cells. These findings provide new insights into the immunological basis of carrier-mediated anti-CPS immunity and may contribute to the development of more effective CPS-based vaccines.
Article
Chemistry, Analytical
Raine Garrido, Barbara Baro, Jean Pierre Soubal, Darielys Santana
Summary: This study presents an improved quantitative P-31-NMR methodology for the quantification of C-polysaccharide in capsular polysaccharide preparations, allowing discrimination between phosphocholine residues linked in different positions. The method was successfully applied to samples of vaccine serotypes, showing good quantification performance with a signal/noise ratio of 16:1. Repeatability and intermediate precision evaluation demonstrated the method's stability, while also providing information on the structural identity of phosphate contained in capsular polysaccharides and C-polysaccharide species.
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
(2021)
Article
Microbiology
Joshua D. Quinn, Eric H. Weening, Taryn A. Miner, Virginia L. Miller
JOURNAL OF BACTERIOLOGY
(2019)
Article
Immunology
Melissa Ellermann, Raad Z. Gharaibeh, Laura Fulbright, Belgin Dogan, Lyndsey N. Moore, Christopher A. Broberg, Lacey R. Lopez, Aaron M. Rothemich, Jeremy W. Herzog, Allison Rogala, Ilyssa O. Gordon, Florian Rieder, Cory R. Brouwer, Kenneth W. Simpson, Christian Jobin, R. Balfour Sartor, Janelle C. Arthur
INFECTION AND IMMUNITY
(2019)
Review
Genetics & Heredity
Daniel R. Matute, Victoria E. Sepulveda
FUNGAL GENETICS AND BIOLOGY
(2019)
Article
Microbiology
Kara R. Eichelberger, Victoria E. Sepulveda, John Ford, Sara R. Selitsky, Piotr A. Mieczkowski, Joel S. Parker, William E. Goldman
Article
Microbiology
Kimberly A. Walker, Logan P. Treat, Victoria E. Sepulveda, Virginia L. Miller
Article
Microbiology
Grant S. Jones, Victoria E. Sepulveda, William E. Goldman
Article
Microbiology
Heidi Mavengere, Kathleen Mattox, Marcus M. Teixeira, Victoria E. Sepulveda, Oscar M. Gomez, Orville Hernandez, Juan McEwen, Daniel R. Matute
Review
Biochemistry & Molecular Biology
Robert B. Bourret, Emily N. Kennedy, Clay A. Foster, Victoria E. Sepulveda, William E. Goldman
Summary: Bacterial two-component regulatory systems mediate signal transduction by phosphoryl group transfer, and fungal sensor kinases exhibit a similar domain structure. However, fungi generally encode more sensor kinases than Hpts, leading to a discrepancy between assumed phosphorelay inputs and outputs. This suggests that most fungal sensor kinases may not participate in phosphorelays.
TRENDS IN MICROBIOLOGY
(2021)
Article
Microbiology
Joshua D. Quinn, Eric H. Weening, Virginia L. Miller
Summary: Yersinia pestis utilizes PsaF as a pH sensor to control psaA expression and virulence by enhancing the stability of PsaE. This study provides insight into the mechanisms bacteria use to sense pH and regulate virulence gene expression.
JOURNAL OF BACTERIOLOGY
(2021)
Article
Microbiology
Lacey R. Lopez, Cassandra J. Barlogio, Christopher A. Broberg, Jeremy Wang, Janelle C. Arthur
Summary: Inflammatory bowel diseases and inflammation-associated colorectal cancer are linked to an increase in adherent-invasive Escherichia coli (AIEC) in the gut microbiota. A study found that the pro-inflammatory and pro-carcinogenic AIEC strain NC101 is unable to grow in minimal media due to a nicotinic acid auxotrophy. This auxotrophy is caused by a missense mutation in the nadA gene, which is involved in de novo nicotinamide adenine dinucleotide biosynthesis, in NC101. Fixing this mutation restored NC101's ability to grow without affecting its pathogenic functions.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Materials Science, Biomaterials
Sara E. Maloney, Christopher A. Broberg, Quincy E. Grayton, Samantha L. Picciotti, Hannah R. Hall, Shannon M. Wallet, Robert Maile, Mark H. Schoenfisch
Summary: In this study, two glycosaminoglycan (GAG) biopolymers were chemically modified to release nitric oxide (NO) for wound healing. The released NO showed broad spectrum bactericidal action and anti-inflammatory mechanisms. The adhesion and proliferation properties of the modified GAGs were also important factors in selecting wound healing candidates.
ACS BIOMATERIALS SCIENCE & ENGINEERING
(2022)