Soil bacteria accumulate polyesters (typically poly([R]-3-hydroxybutyrate (PHB), in which one end of the chain terminates with a carboxyl group) in the form of hydrated, amorphous nanogranules in cells. However, it is not clear what drives the structure of these biomaterials inside bacterial cells. Here, we determined that calcium guides intracellular formation of PHB nanogranules. Our systematic study using the surface zeta potential measurement and the carboxyl-specific SYTO-62 dye binding assay showed that the terminal carboxyl is not exposed to the granule surface but is buried inside native "unit-granules" comprising the mature granule. Extracellular Ca was found to mediate the formation of these PHB unit-granules, with uptaken Ca stored inside the granules. Comparative [Ca]-dependent fluorescence spectroscopy revealed that the native granules in Cupriavidus necator H16 act as a Ca storage system, presumably for the regulation of its cytosolic Ca level, but those from recombinant Escherichia coli do not. This study reveals intimate links between Ca and native granule formation, and establishes a novel mechanism that intracellular PHB granules function as Ca storage in order to relieve soil bacteria from Ca stress.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6401383 | PMC |
http://dx.doi.org/10.1038/s41598-019-40097-5 | DOI Listing |
Appl Environ Microbiol
December 2024
Department of Gastrocolorectal Surgery, General Surgery Center, The First Hospital of Jilin University, Changchun, Jilin, China.
In confronting the significant challenge posed by multidrug-resistant (MDR) pathogens, particularly methicillin-resistant (MRSA), the development of innovative anti-infective strategies is essential. Our research focuses on sortase A (SrtA), a vital enzyme for anchoring surface proteins in . We discovered that plantamajoside (PMS), a phenylpropanoid glycoside extracted from .
View Article and Find Full Text PDFmSphere
December 2024
Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, School of Pharmacy, Chengdu University, Chengdu, China.
is a prominent Gram-negative and encapsulated opportunistic pathogen that causes a multitude of infections such as severe respiratory and healthcare-associated infections. Despite the widespread anti-microbial resistance and the high mortality rate, currently, no clinically vaccine is approved for battling . To date, messenger RNA (mRNA) vaccine is one of the most advancing technologies and are extensively investigated for viral infection, while infrequently applied for prevention of bacterial infections.
View Article and Find Full Text PDFMicrobiol Spectr
December 2024
Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China.
Unlabelled: RamA is an intrinsic regulator in , belonging to the AraC family of transcription factors and conferring a multidrug resistance phenotype, especially for tetracycline-class antibiotics. The ATP-binding cassette transporters MlaFEDCB in bacteria play essential roles in functions essential for cell survival and intrinsic resistance to many antibiotics. We found deletion of resulted in a fivefold decrease in the transcriptional levels of the operon.
View Article and Find Full Text PDFClin Chem Lab Med
January 2025
117303 Graduate Program in Health Sciences, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Brazil.
Objectives: To evaluate urinalysis parameters useful for identifying mixed cultures in urine culture using an automated urinary particle analyzer to assess quality indicators (QIs) for urine sample contamination.
Methods: A retrospective observational cross-sectional study was conducted with 2,527 urine samples from patients of a quaternary hospital in Brazil. Urine samples were processed simultaneously in Sysmex UF-5000 flow cytometry analyzer (urinalysis) and MALDI-TOF (culture).
Front Mol Neurosci
December 2024
Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States.
Introduction: The prostate is densely innervated like many visceral organs and glands. However, studies to date have focused on sympathetic and parasympathetic nerves and little attention has been given to the presence or function of sensory nerves in the prostate. Recent studies have highlighted a role for sensory nerves beyond perception of noxious stimuli, as anterograde release of neuropeptides from sensory nerves can affect vascular tone and local immune responses.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!