Selected mutant strains of Klebsiella pneumoniae that are unable to fix nitrogen have been characterized according to nitrogenase component activity as well as antigenic cross-reacting material. The lesions in these strains have been mapped by transduction, and the results indicate that there are at least five genes specifically responsible for nitrogen fixation in vivo. Besides genes that specify the structure of the two nitrogenase components, there is a gene for a factor that is required for component I activity and a gene that codes for a factor possibly involved in electron transport to component II. A mutation in another site does not allow the organism to produce either of the nitrogenase components. All of these genes are co-transducible with the gene that specifics the structure of histidinol dehydrogenase.
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http://dx.doi.org/10.1128/jb.121.3.759-765.1975 | DOI Listing |
Environ Int
January 2025
Ineos Oxford Institute for Antimicrobial Research, Department of Biology, University of Oxford, Oxford, United Kingdom; Division of Infection and Immunity, Department of Medical Microbiology, Heath Campus, Cardiff University, Cardiff, United Kingdom. Electronic address:
The dissemination of antimicrobial resistant (AMR) bacteria by flies in hospitals is concerning as nosocomial AMR infections pose a significant threat to public health. This threat is compounded in low- and middle-income countries (LMICs) by several factors, including limited resources for sufficient infection prevention and control (IPC) practices and high numbers of flies in tropical climates. In this pilot study, 1,396 flies were collected between August and September 2022 from eight tertiary care hospitals in six cities (Abuja, Enugu, Kaduna, Kano, Lagos and Sokoto) in Nigeria.
View Article and Find Full Text PDFViruses
January 2025
Laboratory of Molecular Biology, G. Eliava Institute of Bacteriophages, Microbiology and Virology, 0160 Tbilisi, Georgia.
The rapid worldwide spread of antibiotic resistance is quickly becoming an increasingly concerning problem for human healthcare. Non-antibiotic antibacterial agents are in high demand for many Gram-negative bacterial pathogens, including . -targeting phages are among the most promising alternative therapy options.
View Article and Find Full Text PDFViruses
January 2025
Laboratory of Molecular Microbiology, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.
is an important opportunistic pathogen often resistant to antibiotics. Specific phages can be useful in eliminating infection caused by . phage vB_KlebPS_265 (KlebP_265) and its host strain were isolated from the sputum of a patient with infection.
View Article and Find Full Text PDFPathogens
January 2025
MicroART-Antibiotic Resistance Team, Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal.
One of the significant challenges facing modern medicine is the rising rate of antibiotic resistance, which impacts public health, animal health, and environmental preservation. Evaluating antibiotic resistance in wildlife and their environments is crucial, as it offers essential insights into the dynamics of resistance patterns and promotes strategies for monitoring, prevention, and intervention. and genera isolates were recovered from fecal samples of wild animals and environmental samples using media without antibiotic supplementation.
View Article and Find Full Text PDFPathogens
January 2025
Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.
The emergence of hypervirulent and carbapenem-resistant hypermucoviscous strains presents a significant public health challenge due to their increased virulence and resistance to multiple antibiotics. This study evaluates the antibiotic susceptibility patterns and virulence profiles of classical and hypervirulent strains isolated from various clinical samples. A total of 500 clinical samples were collected from patients at the Mardan Medical Complex and Ayub Medical Complex in KPK between July 2022 and June 2024.
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