Bacillus anthracis makes highly stable, heat-resistant spores which remain viable for decades. Effect of various stress conditions on sporulation in B. anthracis was studied in nutrient-deprived and sporulation medium adjusted to various pH and temperatures. The results revealed that sporulation efficiency was dependent on conditions prevailing during sporulation. Sporulation occurred earlier in culture sporulating at alkaline pH or in PBS than control. Spores formed in PBS were highly sensitive towards spore denaturants whereas, those formed at 45 degrees C were highly resistant. The decimal reduction time (D-10 time) of the spores formed at 45 degrees C by wet heat, 2 M HCl, 2 M NaOH and 2 M H(2)O(2) was higher than the respective D-10 time for the spores formed in PBS. The dipicolinic acid (DPA) content and germination efficiency was highest in spores formed at 45 degrees C. Since DPA is related to spore sensitivity towards heat and chemicals, the increased DPA content of spores prepared at 45 degrees C may be responsible for increased resistance to wet heat and other denaturants. The size of spores formed at 45 degrees C was smallest amongst all. The study reveals that temperature, pH and nutrient availability during sporulation affect properties of B. anthracis spores.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s00203-007-0295-9 | DOI Listing |
Int J Syst Evol Microbiol
January 2025
Department of Microbiology, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand.
A novel strain DW16-2, isolated from duckweed (), was taxonomically studied in detail. The analysis based on its 16S rRNA gene sequence revealed that the strain was most closely related to Y8 (98.8%), followed by YIM 61452 (98.
View Article and Find Full Text PDFAnn Biol Clin (Paris)
January 2025
Laboratoire Clostridioides difficile associé au Centre National de Référence des bactéries anaérobies et du botulisme, Hôpital Saint-Antoine, Assistance Publique Hôpitaux de Paris, 184 rue du Faubourg Saint-Antoine, 75012 Paris France, UMR-S 1139 3PHM, Université Paris Cité, Paris, France.
Clostridioides difficile is a Gram-positive, spore-forming anaerobic enteropathogen responsible for a wide spectrum of clinical diseases ranging from mild diarrhoea to pseudomembranous colitis. It is the first cause of healthcare-associated diarrhoeas, but community-associated Clostridioides difficile infections (CDI) are increasingly reported in patients without the common risk factors (age > 65 years, previous antibiotic treatment). The main C.
View Article and Find Full Text PDFScience
January 2025
Antibody Biology Unit, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
The most advanced monoclonal antibodies (mAbs) and vaccines against malaria target the central repeat region or closely related sequences within the circumsporozoite protein (PfCSP). Here, using an antigen-agnostic strategy to investigate human antibody responses to whole sporozoites, we identified a class of mAbs that target a cryptic PfCSP epitope that is only exposed after cleavage and subsequent pyroglutamylation (pGlu) of the newly formed N terminus. This pGlu-CSP epitope is not targeted by current anti-PfCSP mAbs and is not included in the licensed malaria vaccines.
View Article and Find Full Text PDFVet Med Int
December 2024
Department of Biology, Aksum University, Axum, Ethiopia.
Safety and quality of milk and milk products are an increasing concern worldwide. Milk and milk products are major causes of milk-borne diseases due to contamination with microorganisms resulting from a lack of standard milk handling procedures and hygienic practices. Thus, the study aims to investigate the microbial quality and safety of cow milk and milk products and isolate some bacteria in Tigray.
View Article and Find Full Text PDFACS Synth Biol
December 2024
Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States.
Elevated lactate concentrations are implicated in various acute and chronic diseases, such as sepsis and mitochondrial dysfunction, respectively. Conversely, ineffective lactate clearance is associated with poor clinical prognoses and high mortality in these diseases. While several groups have proposed using small molecule inhibitors and enzyme replacement to reduce circulating lactate, there are few practical and effective ways to manage this condition.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!