-
Current Opinion in Plant Biology Feb 2017Two major conducting tissues in plants, phloem and xylem, are composed of highly specialized cell types adapted to long distance transport. Sieve elements (SEs) in the... (Review)
Review
Two major conducting tissues in plants, phloem and xylem, are composed of highly specialized cell types adapted to long distance transport. Sieve elements (SEs) in the phloem display a thick cell wall, callose-rich sieve plates and low cytoplasmic density. SE differentiation is driven by selective autolysis combined with enucleation, after which the plasma membrane and some organelles are retained. By contrast, differentiation of xylem tracheary elements (TEs) involves complete clearance of the cellular components by programmed cell death followed by autolysis of the protoplast; this is accompanied by extensive deposition of lignin and cellulose in the cell wall. Emerging molecular data on TE and SE differentiation indicate a central role for NAC and MYB type transcription factors in both processes.
Topics: Arabidopsis; Arabidopsis Proteins; Cell Differentiation; Phloem; Plant Development; Plant Proteins; Transcription Factors; Xylem
PubMed: 27794261
DOI: 10.1016/j.pbi.2016.10.007 -
Scientific Reports Jul 2021Kluyveromyces marxianus is a yeast that could be identified from kefir and can use a broad range of substrates, such as glucose and lactate, as carbon sources. The...
Kluyveromyces marxianus is a yeast that could be identified from kefir and can use a broad range of substrates, such as glucose and lactate, as carbon sources. The lactate produced in kefir culture can be a substrate for K. marxianus. However, the complexity of the kefir microbiota makes the traits of K. marxianus difficult to study. In this research, we focused on K. marxianus cultured with lactate as the sole carbon source. The optimal growth and released protein in lactate culture were determined under different pH conditions, and the LC-MS/MS-identified proteins were associated with the tricarboxylic acid cycle, glycolysis pathway, and cellular stress responses in cells, indicating that autolysis of K. marxianus had occurred under the culture conditions. The abundant glyceraldehyde-3-phosphate dehydrogenase 1 (GAP1) was cocrystallized with other proteins in the cell-free fraction, and the low transcription level of the GAP1 gene indicated that the protein abundance under autolysis conditions was dependent on protein stability. These results suggest that lactate induces the growth and autolysis of K. marxianus, releasing proteins and peptides. These findings can be fundamental for K. marxianus probiotic and kefir studies in the future.
Topics: Culture Media; Electrophoresis, Polyacrylamide Gel; Fungal Proteins; Gene Expression Regulation, Fungal; Hydrogen-Ion Concentration; Kefir; Kluyveromyces; Lactic Acid; Multilocus Sequence Typing; Mycological Typing Techniques; Tandem Mass Spectrometry
PubMed: 34267270
DOI: 10.1038/s41598-021-94101-y -
Frontiers in Microbiology 2023
PubMed: 37234522
DOI: 10.3389/fmicb.2023.1199578 -
International Journal of Antimicrobial... Oct 2023The pathogenicity of Staphylococcus epidermidis is largely attributed to its exceptional ability to form biofilms. Here, we report that mupirocin, an antimicrobial agent...
The pathogenicity of Staphylococcus epidermidis is largely attributed to its exceptional ability to form biofilms. Here, we report that mupirocin, an antimicrobial agent widely used for staphylococcal decolonization and anti-infection, strongly stimulates the biofilm formation of S. epidermidis. Although the polysaccharide intercellular adhesin (PIA) production was unaffected, mupirocin significantly facilitated extracellular DNA (eDNA) release by accelerating autolysis, thereby positively triggering cell surface attachment and intercellular agglomeration during biofilm development. Mechanistically, mupirocin regulated the expression of genes encoding for the autolysin AtlE as well as the programmed cell death system CidA-LrgAB. Critically, through gene knockout, we found out that deletion of atlE, but not cidA or lrgA, abolished the enhancement of biofilm formation and eDNA release in response to mupirocin treatment, indicating that atlE is required for this effect. In Triton X-100 induced autolysis assay, mupirocin treated atlE mutant displayed a slower autolysis rate compared with the wild-type strain and complementary strain. Therefore, we concluded that subinhibitory concentrations of mupirocin enhance the biofilm formation of S. epidermidis in an atlE dependent manner. This induction effect could conceivably be responsible for some of the more unfavourable outcomes of infectious diseases.
Topics: Staphylococcus epidermidis; Mupirocin; Biofilms; Staphylococcus; Virulence; Bacterial Proteins
PubMed: 37385560
DOI: 10.1016/j.ijantimicag.2023.106904 -
Microbiology Spectrum Jun 2023Staphylococcus aureus is an important human pathogen and brings about many community-acquired, hospital-acquired, and biofilm-associated infections worldwide. It tends...
Staphylococcus aureus is an important human pathogen and brings about many community-acquired, hospital-acquired, and biofilm-associated infections worldwide. It tends to form biofilms, triggering the release of toxins and initiating resistance mechanisms. As a result of the development of S. aureus tolerance to antibiotics, there are few drugs can availably control biofilm-associated infections. In this study, we synthesized a novel small-molecule compound CY-158-11 (CHClNOSe) and proved its inhibitory effect on the biofilm formation of S. aureus at a subinhibitory concentration (1/8 MIC). The subinhibitory concentration of CY-158-11 not only did not affect the growth of bacteria but also had no toxicity to A549 cells or G. mellonella. Total biofilm biomass was investigated by crystal violet staining, and the results were confirmed by SYTO 9 and PI staining through confocal laser scanning microscopy. Moreover, CY-158-11 effectively prevented initial attachment and repressed the production of PIA instead of autolysis. RT-qPCR analysis also exhibited significant suppression of the genes involved in biofilm formation. Taken together, CY-158-11 exerted its inhibitory effects against the biofilm formation in S. aureus by inhibiting cell adhesion and the expression of related to PIA production. Most bacteria exist in the form of biofilms, often strongly adherent to various surfaces, causing bacterial resistance and chronic infections. In general, antibacterial drugs are not effective against biofilms. The small-molecule compound CY-158-11 inhibited the biofilm formation of S. aureus at a subinhibitory concentration. By hindering adhesion and PIA-mediated biofilm formation, CY-158-11 exhibits antibiofilm activity toward S. aureus. These findings point to a novel therapeutic agent for combating intractable S. aureus-biofilm-related infections.
Topics: Humans; Staphylococcus aureus; Anti-Bacterial Agents; Biofilms; Staphylococcal Infections; Gentian Violet; Microbial Sensitivity Tests
PubMed: 37166296
DOI: 10.1128/spectrum.00045-23 -
Frontiers in Microbiology 2021Microorganisms are widely utilized for the treatment of wastewater in activated sludge systems. However, the uncontrolled growth of filamentous bacteria leads to bulking...
Microorganisms are widely utilized for the treatment of wastewater in activated sludge systems. However, the uncontrolled growth of filamentous bacteria leads to bulking and adversely affects wastewater treatment efficiency. To clarify the nutrient requirements for filament formation, we track the growth of a filamentous bacterium, SP-6 in different nutrient-limited conditions using a high aspect-ratio microfluidic chamber to follow cell-chain elongation and sheath formation. We find that limitations in Na, K, and Fe yield no observable changes in the elongation of cell chains and sheath formation, whereas limitations of C, N, P, or vitamins lead to more pronounced changes in filament morphology; here we observe the appearance of partially empty filaments with wide intercellular gaps. We observe more dramatic differences when SP-6 cells are transferred to media lacking Mg and Ca. Loss of Mg results in cell autolysis, while removal of Ca results in the catastrophic disintegration of the filaments. By simultaneously limiting both carbon and Ca sources, we are able to stimulate planktonic cell generation. These findings paint a detailed picture of the ecophysiology of , which may lead to improved control over the unchecked growth of deleterious filamentous bacteria in water purification systems.
PubMed: 34248917
DOI: 10.3389/fmicb.2021.691563 -
Romanian Journal of Morphology and... 2019Blaise Pascal (1623-1662) was a French philosopher, who wrote the Pensées, a collection of "thoughts" about the apparent insignificance of human existence. In the last... (Review)
Review
Blaise Pascal (1623-1662) was a French philosopher, who wrote the Pensées, a collection of "thoughts" about the apparent insignificance of human existence. In the last three centuries, it was claimed that his disease was mental. Hysteria, melancholia, and post-traumatic neurosis were taken into consideration, but none of the proposed diagnoses seems to be satisfactory. The aim of our work is to identify Pascal's mysterious illness. We correlated the symptoms of the indirect anamnesis (Pascal's letters to friends, letters and biographies made by his sisters and granddaughter) and autopsy data. Based on these data, we consider that Pascal's illness, which has affected him all his life and caused his death, was celiac disease, the diagnosis being supported by: childhood abdominal pain with gradual progression to neurological manifestations in his middle-age, which were expressed by migraine-type headaches, peripheral neuropathy, epilepsy, neuropsychiatric disorders (depression). The hypothesis of a celiac disease is also argued by autopsy data: lack of closure of the fontanelle due to type D hypovitaminosis, intestinal gangrene because celiac disease accelerates the post-mortem autolysis, gliosis and calcification of the nervous tissue. The second cause of his death was a chronic traumatic subdural hematoma, probably located in the superior temporal region, which was the reason for his left-sided hemianopsia that occurred immediately after a carriage accident. Conclusions: Pascal's philosophy reflects his own inner life, which was deeply influenced by the organic affections he suffered.
Topics: History, 17th Century; Humans; Mental Disorders; Philosophy
PubMed: 32239123
DOI: No ID Found -
Antibiotics (Basel, Switzerland) May 2023Vancomycin and daptomycin are first-line drugs for the treatment of complicated methicillin-resistant (MRSA) infections, including bacteremia. However, their...
Vancomycin and daptomycin are first-line drugs for the treatment of complicated methicillin-resistant (MRSA) infections, including bacteremia. However, their effectiveness is limited not only by their resistance to each antibiotic but also by their associated resistance to both drugs. It is unknown whether novel lipoglycopeptides can overcome this associated resistance. Resistant derivatives from five strains were obtained during adaptive laboratory evolution with vancomycin and daptomycin. Both parental and derivative strains were subjected to susceptibility testing, population analysis profiles, measurements of growth rate and autolytic activity, and whole-genome sequencing. Regardless of whether vancomycin or daptomycin was selected, most of the derivatives were characterized by a reduced susceptibility to daptomycin, vancomycin, telavancin, dalbavancin, and oritavancin. Resistance to induced autolysis was observed in all derivatives. Daptomycin resistance was associated with a significant reduction in growth rate. Resistance to vancomycin was mainly associated with mutations in the genes responsible for cell wall biosynthesis, and resistance to daptomycin was associated with mutations in the genes responsible for phospholipid biosynthesis and glycerol metabolism. However, mutations in and were detected in derivatives selected for both antibiotics.
PubMed: 37237831
DOI: 10.3390/antibiotics12050928 -
Journal of Clinical Medicine Jan 2023() is a Gram-positive, facultative anaerobic bacterium that is highly adaptable to its environment. In humans, it can cause serious infections with biofilm formation.... (Review)
Review
() is a Gram-positive, facultative anaerobic bacterium that is highly adaptable to its environment. In humans, it can cause serious infections with biofilm formation. With increasing attention on its health threat, prevention and control of biofilm formation in have been observed. Many factors including polysaccharides as well as autolysis, proteases, and eDNA regulate biofilm formation. Those contributors are regulated by several important regulatory systems involving the two-component signal transduction system (TCS) for its adaptation to the environment. Highly conserved WalRK as one of 17 TCSs is the only essential TCS in . In addition to biofilm formation, various metabolisms, including cell wall construction, drug resistance, as well as interactions among regulatory systems and resistance to the host immune system, can be modulated by the WalRK system. Therefore, WalRK has been identified as a key target for infection control. In the present review, the regulation of WalRK on pathogenesis and associated therapeutic strategies are demonstrated.
PubMed: 36769415
DOI: 10.3390/jcm12030767 -
Polymers Sep 2022Seafood is a highly economical product worldwide. Primary modes of deterioration include autolysis, oxidation of protein and lipids, formation of biogenic amines and... (Review)
Review
Seafood is a highly economical product worldwide. Primary modes of deterioration include autolysis, oxidation of protein and lipids, formation of biogenic amines and melanosis, and microbial deterioration. These post-harvest losses can be properly handled if the appropriate packaging technology has been applied. Therefore, it is necessary for packaging deterioration relevance to be clearly understood. This review demonstrates recent polymeric packaging technology for seafood products. Relationship between packaging and quality deterioration, including microbial growth and chemical and biochemical reactions, are discussed. Recent technology and trends in the development of seafood packaging are demonstrated by recent research articles and patents. Development of functional polymers for active packaging is the largest area for seafood applications. Intelligent packaging, modified atmosphere packaging, thermal insulator cartons, as well as the method of removing a fishy aroma have been widely developed and patented to solve the specific and comprehensive quality issues in seafood products. Many active antioxidant and antimicrobial compounds have been found and successfully incorporated with polymers to preserve the quality and monitor the fish freshness. A thermal insulator has also been developed for seafood packaging to preserve its freshness and avoid deterioration by microbial growth and enzymatic activity. Moreover, the enhanced biodegradable tray is also innovative as a single or bulk fish container for marketing and distribution. Accordingly, this review shows emerging polymeric packaging technology for seafood products and the relevance between packaging and seafood qualities.
PubMed: 36145850
DOI: 10.3390/polym14183706