scholarly journals Species-dependent protoplast enlargement involves different types of vacuole generation in bacteria

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sawako Takahashi ◽  
Marin Mizuma ◽  
Satoshi Kami ◽  
Hiromi Nishida
Keyword(s):  
Plasma Membrane ◽  
Enterococcus Faecalis ◽  
Bacterial Cell ◽  
Early Stage ◽  
Cell Enlargement ◽  
Gram Positive ◽  
Gram Negative ◽  
Different Types ◽  
Spherical Structures ◽  
Vacuolar Membranes

Abstract Vacuole generation occurs frequently during the enlargement of bacterial protoplasts and spheroplasts. Gram-positive Enterococcus faecalis protoplasts and gram-negative Lelliottia amnigena spheroplasts had large and small vacuoles inside the cytoplasm, respectively. Although no vacuoles were found at the early stage of cell enlargement, all enlarged cells used in the microinjection procedures had vacuoles. The plasma membrane of L. amnigena was more flexible than that of E. faecalis. In addition, E. faecalis protoplasts had unique discoidal structures as well as spherical structures in the cytoplasm. Our findings showed that the number of vacuoles increased as the L. amnigena plasma membrane expanded and that the size of vacuoles increased as the E. faecalis plasma membrane expanded, suggesting that bacterial cell enlargement involved vacuole generation. Thus, biosynthesis of the plasma and vacuolar membranes was synchronous with the bacterial cell enlargement. Differences in the plasma membrane flexibility might influence the different types of vacuole generation.

Microanatomy of the Periplasm of Bacillus Licheniformis

1971 ◽  
Vol 29 ◽  
pp. 262-263
Author(s):  
B.K. Ghosh
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacillus Licheniformis ◽  
External Environment ◽  
Permeability Barrier ◽  
Periplasmic Space ◽  
Modified Technique ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

scholarly journals Molecular Dynamics Simulation of the Interaction of Two Linear Battacin Analogs with Model Gram-Positive and Gram-Negative Bacterial Cell Membranes

ACS Omega ◽  
2020 ◽  
Author(s):  
Aparajita Chakraborty ◽  
Elisey Kobzev ◽  
Jonathan Chan ◽  
Gayan Heruka de Zoysa ◽  
Vijayalekshmi Sarojini ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Bacterial Cell ◽  
Cell Membranes ◽  
Dynamics Simulation ◽  
Gram Positive ◽  
Gram Negative

scholarly journals Factors That Affect the Enlargement of Bacterial Protoplasts and Spheroplasts

2020 ◽  
Vol 21 (19) ◽  
pp. 7131
Author(s):  
Hiromi Nishida
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacterial Cell ◽  
Metal Ion ◽  
Bacterial Species ◽  
Bacterial Cells ◽  
Cell Enlargement ◽  
Ion Composition ◽  
Gene Manipulation ◽  
Peptidoglycan Biosynthesis

Cell enlargement is essential for the microinjection of various substances into bacterial cells. The cell wall (peptidoglycan) inhibits cell enlargement. Thus, bacterial protoplasts/spheroplasts are used for enlargement because they lack cell wall. Though bacterial species that are capable of gene manipulation are limited, procedure for bacterial cell enlargement does not involve any gene manipulation technique. In order to prevent cell wall resynthesis during enlargement of protoplasts/spheroplasts, incubation media are supplemented with inhibitors of peptidoglycan biosynthesis such as penicillin. Moreover, metal ion composition in the incubation medium affects the properties of the plasma membrane. Therefore, in order to generate enlarged cells that are suitable for microinjection, metal ion composition in the medium should be considered. Experiment of bacterial protoplast or spheroplast enlargement is useful for studies on bacterial plasma membrane biosynthesis. In this paper, we have summarized the factors that influence bacterial cell enlargement.

Evolution of Our Experience in Diagnosis and Therapy for Urinary Infections

2009 ◽  
Vol 76 (2) ◽  
pp. 140-143
Author(s):  
R. Pizzorno ◽  
A. Simonato ◽  
M. Esposito ◽  
T. Montanaro ◽  
M. Mussap ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Empirical Therapy ◽  
Enterococcus Species ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Diagnosis And Therapy ◽  
Urinary Infections ◽  
Spectrum Activity

The therapy for urinary infections is advised according to the antibiogram; the symptoms request an empirical therapy based on urinary infections knowledge and drugs spectrum activity. We considered the urinoculture performed on 3834 patients, 3012 male and 822 female, hospitalized in our Institute in the period between 01/01/2005 and 31/10/2006; 444 of these were positive (12.7 % - 451 bacterial strains). Table 1: bacterial strains isolaed. We reported some evaluations obtained by antibiogram. E. coli strains Ciprofloxacin sensitive resulted in 60% of cases. Enterococcus species and Enterococcus faecalis strains Ampicillin sensitive resulted in 96.4% and 100% of cases, respectively. In this study there is a Gram negative prevalence, whereas we had previously observed an equivalence between Gram negative and Gram positive (p 0.001). These data are useful for empirical therapy.

Survival of some non-starter bacteria in naturally ripened and enzyme-accelerated Cheddar cheese

1988 ◽  
Vol 55 (4) ◽  
pp. 597-602 ◽  
Author(s):  
Lydia Bautista ◽  
Rohan G. Kroll
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Enterococcus Faecalis ◽  
Enzyme System ◽  
Cheddar Cheese ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Ripening Period ◽  
Gram Positive Bacteria

SummaryEffects of the addition of a proteinase (Neutrase 1–5S) and a peptidase (aminopeptidase DP-102) as agents for accelerating the ripening of Cheddar cheese on the survival of some non-starter bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coliand aSalmonellasp.) were studied throughout a 4-month ripening period. The enzymes were found to have no significant effect on the survival of the Gram-positive bacteria but some significant effects were observed, at some stages of the ripening period, with the Gram-negative bacteria in that lower levels were recovered from cheeses treated with the enzyme system.

scholarly journals Polyethylene Glycol6000/carbon Nanodots as Fluorescent Bioimaging Agents

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 677 ◽  
Author(s):  
Chun-Chieh Fu ◽  
Chun-Yung Wu ◽  
Chih-Ching Chien ◽  
Tai-Hao Hsu ◽  
Shih-Fu Ou ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Carbon Quantum Dots ◽  
Carbon Nanodots ◽  
Gram Negative Bacteria ◽  
Fluorescent Properties ◽  
Gram Positive ◽  
Gram Negative ◽  
Different Types ◽  
Living Organisms ◽  
Surface Modified

Photoluminescent nanomaterials have immense potential for use in biological systems due to their excellent fluorescent properties and small size. Traditional semiconductor quantum dots are heavy-metal-based and can be highly toxic to living organisms, besides their poor photostability and low biocompatibility. Nano-sized carbon quantum dots and their surface-modified counterparts have shown improved characteristics for imaging purposes. We used 1,3, 6-trinitropyrene (TNP) and polyethylene glycol6000 (PEG6000) in a hydrothermal method to prepare functional polyethylene glycol6000/carbon nanodots (PEG6000/CDs) and analyzed their potential in fluorescent staining of different types of bacteria. Our results demonstrated that PEG6000/CDs stained the cell pole and septa of gram-positive bacteria B. Subtilis and B. thuringiensis but not those of gram-negative bacteria. The optimal concentration of these composite nanodots was approximately 100 ppm and exposure times varied across different bacteria. The PEG6000/CD composite had better photostability and higher resistance to photobleaching than the commercially available FM4-64. They could emit two wavelengths (red and green) when exposed to two different wavelengths. Therefore, they may be applicable as bioimaging molecules. They can also be used for differentiating different types of bacteria owing to their ability to differentially stain gram-positive and gram-negative bacteria.

scholarly journals Phagocyte chase behaviours: discrimination between Gram-negative and Gram-positive bacteria by amoebae

2019 ◽  
Vol 15 (1) ◽  
pp. 20180607 ◽  
Author(s):  
Ghazal Rashidi ◽  
Elizabeth A. Ostrowski
Keyword(s):  
Prior Work ◽  
Free Living ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Different Types ◽  
Soil Amoeba ◽  
Response Profiles ◽  
Mammalian Immune System ◽  
Geographical Locations

Phagocytes are cells that pursue, engulf and kill bacteria. They include macrophages and neutrophils of the mammalian immune system, as well as free-living amoebae that hunt and engulf bacteria for food. Phagocytosis can result in diverse outcomes, ranging from sustenance to infection and colonization by either pathogens or beneficial symbionts—and thus, discrimination may be necessary to seek out good bacteria while avoiding bad ones. Here we tested whether the soil amoeba Dictyostelium discoideum can discriminate among different types of bacteria using behavioural assays where amoebae were presented with paired choices of different bacteria. We observed variation in the extent to which the amoebae pursued different types of bacteria, as well as preferential migration towards Gram-negative compared with Gram-positive bacteria. Response profiles were similar for amoebae that originated from different geographical locations, suggesting that chase preference is conserved across much of the species range. While prior work has demonstrated that bacteria use chemotaxis to seek out amoebae they colonize, our work suggests that the opposite also occurs—amoebae can preferentially direct themselves to particular bacteria in the environment. Preferential sensing and response may help to explain why some amoeba–bacteria associations are more common in nature than others.

The caceum of the Koala, Phascolarctos cinereus: Light, scanning and transmission electron microscopic observations on its epithelium and flora

1978 ◽  
Vol 26 (2) ◽  
pp. 249 ◽  
Author(s):  
RA McKenzie
Keyword(s):  
Columnar Epithelium ◽  
Electron Microscopic ◽  
Gram Positive ◽  
Phascolarctos Cinereus ◽  
Gram Negative ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Different Types

The pseudostratified columnar epithelium of the koala caecum is surmounted on its luminal border by a tall palisade fringe of bacteria of different types including Gram-positive and Gram-negative bacilli, cocci and actinomycete-like organisms. Ultrastructure of the epithelium indicates that it absorbs water and nutrients from the caecal lumen, and secretes mucus to lubricate the passage of ingesta.

Gut Flora in Autistic Children as Biomarker for Autism in Thi-Qar Province/Iraq

2020 ◽  
pp. 73-79
Keyword(s):  
Escherichia Coli ◽  
Enterococcus Faecalis ◽  
The Other ◽  
Bacterial Isolates ◽  
Autistic Children ◽  
Gram Positive ◽  
Gram Negative ◽  
Other Hand ◽  
Significant Difference ◽  
Gram Positive Cocci

This is the first study that investigated the microbial factor as biomarker in autistic children and discuss roles of this factor in the pathogenesis of autism. The participants in current study were 145 persons, only 50 sample of stool could collected (35 autistic children and 15 healthy children). Autistic children were attended to autism unit at Disabled Hospital in Thi-Qar province, Iraq during the period from January to November 2016. The results showed males (81%) more than female (19%) with ratio 4:1 and also results explain the age group of 3-5 years recorded the highest percentage (41.05%). Distribution of autistic children according to sibling showed six were brotherly with occurrence rate 6.3%. Stool samples were subjected to examination and culture. The total aerobic count of isolated bacteria was 140 isolates. Gram-negative isolates were identified by API Enterobacteriaceae system. The results were Escherichia coli, Enterobacter cloacae, Klebsiella pneumonia, Pseudomonas aeruginosa and Proteus mirabilis with percentage 38.5%, 19.23%, 11.53%,7.69%, and 3.84% respectively. On the other hand, gram positive cocci isolates included Enterococcus faecalis, Staphylococcus aureus and Staph. epidermidis with percentage 11.53%, 4.80% and 2.88% respectively. A significant difference (P≤0.05) was recorded between bacterial isolates. Quantity and quality of isolated bacteria (colony/g *104) were done. E.coli isolates were the highest count with 261*104 colony/g while, Staphylococci epidermidis were recorded the worse colony count with 30*104 colony/g. The quality results showed Escherichia coli the most common gram negative bacterial isolates (38.46%). On the other hand, the highest gram positive cocci isolates were included Enterococcus faecalis (11.53%), with significant difference (P≤0.05) between bacterial isolates. The ability of bacterial isolates to produce histidine decarboxylase was examined on Niven medium. The positive result include colonies with purple halo around them. Only 10 isolates (25%) from all isolates were produce histidine belong to E.coli. On other hand, result of parasite examination explain no parasite in all samples. From this study can conclusion the altered gut microflora may play an essential role in the pathogenesis of autism. Despite the accurate evidence, this etiological heterogeneity is still not recognized by autism researchers, and most studies fail to take it into account.

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