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Bacteria
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
Prokaryotic cells are fundamentally different from eukaryotic cells (Table 15.2). Structure is an important consideration because of the involvement of several structural components as factors of virulence, i.e., the ability of the microbe to cause disease. Figure 15.2 is an idealized schematic drawing of a prokaryotic cell showing structural components. It must be emphasized, however, that not all of the components shown are always present in a single species of bacteria. Keep in mind that all bacterial diseases are interactions between prokaryotic and eukaryotic cells.
Cancer Biology and Genetics for Non-Biologists
Published in Trevor F. Cox, Medical Statistics for Cancer Studies, 2022
All living things are made up of cells, from the simple unicellular amoeba to the complex human composed of about 37 trillion () cells. Cells that contain a nucleus are called eukaryotic cells; cells without a nucleus are called prokaryotic cells. Bacteria are examples of prokaryotic cells. Humans are eukaryotes consisting of eukaryotic cells, such as bone, nerve and stem cells. In fact, there are about 200 types of cells in our bodies. Figure 2.1 shows a typical eukaryotic cell, illustrating its structure. Cells come in different shapes and sizes; neurons in the brain and nervous system are long and thin, blood cells are roughly spherical, some bone cells are cuboidal and columnar while others have many branches. The size of a red blood cell is , the size of a skin cell is , an ovum , whilst the length of some nerve cells can be over .
Gene Expression
Published in Danilo D. Lasic, LIPOSOMES in GENE DELIVERY, 2019
Prokaryotic cells, such as Escherichia coli, contain genetic material in the form of the single DNA molecule. The length of DNA exceeds cell dimensions almost a thousandfold, and the molecule is condensed into a small chromosome. Genetic information, however, is also contained in small episomal plasmids, such as the ones which can confer antibiotic resistance to bacteria. These plasmids contain codes for enzymes which can deactivate drugs. In contrast, in eukaryotic cells, the genetic material is separated from the cytoplasm by the nuclear membrane.
Experimental confirmation of antimicrobial effects of GdYVO4:Eu3+ nanoparticles
Published in Drug Development and Industrial Pharmacy, 2021
Serpil Gonca, Sadin Özdemir, Svetlana Yefimova, Anton Tkachenko, Anatolii Onishchenko, Vladimir Klochkov, Nataliya Kavok, Pavel Maksimchuk, Nadir Dizge, Kasim Ocakoglu
The global character of antibiotic resistance calls for the cooperative approach in combating this challenge to the international public health system. Efficient strategies for targeting the antibiotic resistance include the prevention of misusage and over usage of antimicrobial agents, development of alternative therapeuticals such as antimicrobial peptides, phages and nanomaterials [8–10]. Nanomaterials due to their small size (1–100 nm) and unique properties can enter prokaryotic cells and be toxic to them. The use of nanoparticles (NPs) alone or in combination with conventional antibacterial treatment has been shown to be an effective strategy against the antibacterial resistance, especially multi-drug resistance [11,12]. It is important to note that NPs can target multiple pathways in bacterial cells affecting cell membranes, DNA molecules, disrupting energy metabolism via electron transport chain inhibition, promoting oxidative stress through a reactive oxygen species (ROS)-mediated mechanism, damaging proton efflux pumps, inactivating microbial proteins by stimulating the release of metal ions that bind to thiol groups of proteins, preventing biofilm formation, etc. [13–15]. However, NPs are shown to be toxic to eukaryotic cells [16]. Given this fact, it is of huge importance to develop NPs selectively toxic to prokaryotic cells maintaining a dose-based efficacy-toxicity tradeoff.
Higher accuracy of genotypic identification compared to phenotyping in the diagnosis of coagulase-negative staphylococcus infection in orthopedic surgery
Published in Infectious Diseases, 2020
Gema Muñoz-Gamito, Eva Cuchí, Jordi Roigé, Lucía Gómez, Àngels Jaén, Alfredo Matamala, M. Lluïsa Pedro-Botet, Josep Anton Capdevila, Francesc Anglès, Josefa Pérez
Microbial identification based on genotyping has proven to be more accurate than phenotyping in other clinical scenarios, such as catheter-related infections [2], but the usefulness of this technique has not been investigated in bone and joint infection. Repetitive extragenic palindromic PCR (rep-PCR) is a technique based on amplification and detection of the repetitive DNA characteristically found in microorganisms. These sequences can be used to construct primers that amplify the regions located between consecutive sequences in a genome. In prokaryotic cells, these sequences are short (<200 bp), widely distributed along the entire genome, and do not code for proteins. One of the first sequences described and studied was named REP (repetitive extragenic palindrome). This term has been used to name the technique. Genetic variants in these sequences produce characteristic amplification patterns that can be identified as DNA bands in electrophoresis gels. With the use of rep-PCR, two strains can be identified as being identical with 97% certainty. For this reason, it is the current reference method for identifying virulent strains in nosocomial and community outbreaks [3–5].
A review of co-culture models to study the oral microenvironment and disease
Published in Journal of Oral Microbiology, 2020
Sophie E Mountcastle, Sophie C Cox, Rachel L Sammons, Sara Jabbari, Richard M Shelton, Sarah A Kuehne
Co-culture techniques allow a variety of cell types to be cultivated together, enabling examination of cell–cell interactions [10]. These systems may refer to the culture of two or more eukaryotic cell types together, or eukaryotic and prokaryotic cells. The effectiveness of co-cultures is heavily determined by the choice of experimental setup. Cell–cell interactions in co-cultures are strongly influenced by the extracellular environment, which in turn is influenced by the employed protocol [11]. There are numerous factors that need to be optimised to ensure these systems are representative of the native oral cavity, such as the number of cell populations. Having more than two species can result in unstable systems due to multiple reaction pathways, which may be difficult to monitor, analyse, and interpret [11].