bacterial

Virus

... viruses have also further simplified the study of bacterial genetics and have deepened our understanding of ...plasm of the host cell. The capsid of a phage , a bacterial virus, remains on the outside. In contrast, many viruses that infect animal cells enter the host cel...

Vaccine

...cognition) into human or animal cells, of viral or bacterial DNA . These cells then develop immunity against an infectious agent, without the effects other parts of a weakened agent's DNA might have. As of 2003 , DNA vaccination is still experimental, but shows some promising results. Developing immunit...

Tobacco mosaic virus

...t could be transferred between plants, similar to bacterial infections. However, in 1889, Martinus Beijerinck showed that a filtered, bacteria-free culture medium still contained the infectious agent. The first concrete evidence for its existence was given by Dmitri Ivanowski in 1892. In 1935, Wendell Me...

Tobacco mosaic virus

...t could be transferred between plants, similar to bacterial infections. However, in 1889, Martinus Beijerinck showed that a filtered, bacteria-free culture medium still contained the infectious agent. The first concrete evidence for its existence was given by Dmitri Ivanowski in 1892. In 1935, Wendell Me...

Robert Koch

...ncluding staining and purification techniques, and bacterial growth media, including agar plates and the Petri dish (named after J.R. Petri ), both of which are still used today. With these techniques, he was able to discover the bacterium causing tuberculosis ( Mycobacterium tuberculosis ) in 1882 (h...

Blood type

...n exposed to is unknown. It is believed that some bacterial antigens are similar enough to the A and B glycoproteins , and that antibodies created against the bacteria will react to ABO-incompatible blood cells. Apart from on red blood cells, the ABO antigen is also expressed on the glycoprotein von Wil...

Prophage

...ed status. Its genome can be integrated into the bacterial host chromosome or exists as an extrachromosomal plasmid . When stress in the host is detected, the phage enters its reproductive cycle....

Prokaryote

...umans. Sometimes this leads to a life-threatening bacterial infection, but in many cases the organisms are harmless or even beneficial to the host. Evolution of prokaryotes Main article evolution of prokaryotes It is generally accepted that the first living cells were some form of prokaryote. Fossi...

Plasmid

... plasmid. Figure 4 : Schematic drawing of bacterial conjugation. 1 Chromosomal DNA . 2 Plasmids . 3 Pilus . It is possible for several different types of plasmids to coexist in a single cell, e.g., seven different plasmids have been found in E. coli . On the other hand, related plasmids are o...

Phage

...e they are dormant, by adding new functions to the bacterial genome , a phenomenon called lysogenic conversio... as an alternative to antibiotics for treating bacterial infections—because killing bacteria is what phages do best. There is an extensive library of r...

Outbreak

...hat make people, animals, or plants sick. As with bacterial outbreaks, viral outbreaks are classified as sporadic (occasional occurrence), endemic (regular cases often occurring in a region), epidemic (an unusually high number of cases in a region), or pandemic (a global epidemic). Major human epidemic...

Nutrition

... heat treated (as suggested by Pasteur) to control bacterial disease. Pasteurization was effective against bacteria, but it destroyed the vitamin C, causing a nutritional disease. Other examples of adverse effects of food processing, together with research findings and the need to be cautious in the light of ...

Muscle

...nic syndrome (LEMS). Tetanus and botulism are bacterial infections in which bacterial toxins cause increased or decreased muscle tone, respectively. The myopathies are all diseases af...

Muller's ratchet

...urs when the organism is an endosymbiont , e.g. a bacterial endosymbiont of insects, which is only transmitted to offspring from the mother. Another example is mitochondria and chloroplasts , which are also transmitted only vertically (although, in this case, they are not generally considered a separate o...

Molecular genetics

... and temporal regulation cDNAs imprinting bacterial and phage molecular genetics eukaryotic molecular genetics external links Atlas of Genetics and Cytogenetics in Oncology and Haematology [1]...

Molecular biology

...lasmid. This plasmid can be inserted into either bacterial or animal cells. Introducing DNA into bacterial cells is called transformation , and can be effected by several methods, including electroporation...

Mitochondrion

... cardiolipin , which is usually characteristic of bacterial plasma membranes . The outer mitochondrial membrane contains numerous integral proteins called porins , which contain a relatively large internal channel (about 2-3 nm ) and allow ions and small molecules to move in and out of the mitoch...

Mitochondrion

... cardiolipin , which is usually characteristic of bacterial plasma membranes . The outer mitochondrial membrane contains numerous integral proteins called porins , which contain a relatively large internal channel (about 2-3 nm ) and allow ions and small molecules to move in and out of the mitoch...

Microevolution

...tion are examples of microevolution; for example, bacterial strains that have become resistant to antibiotics . Because microevolution can be observed directly, both pro-evolution and some anti-evolution groups agree that it is a fact of life. See also Speciation , Molecular evolution , Population...

Microbiology

...eneration times (the time needed for division of a bacterial cell in two in optimal conditions; ~30 minutes for...plating , which allowed them to transfer numerous bacterial colonies from their specific locations on one agar-filled petri dish to analogous locations on seve...

Max Delbr

...n 1942, he and Salvador Luria demonstrated that bacterial resistance to virus infection is caused by random mutation and not adaptive change. For that, they were awarded the Nobel Prize in Physiology or Medicine in 1969 , sharing it with Alfred Hershey . From the 1950s on, Delbrck worked on phy...

Life

...raterrestrial life is fossil evidence of possible bacterial life on Mars (via the ALH84001 meteorite). Searches for extraterrestrial life are currently focusing on planets and moons believed to possess liquid water, at present or in the past. Recent evidence from the NASA rovers Spirit and Opportunity...

Lambda phage

...a; takes place at a special attachment site in the bacterial genome, called att λ . The sequence of th...nd requires both the phage protein int and the bacterial protein IHF ( integration host factor ). Both int and IHF bind to att P and built an intras...

Immune system

...s degraded by the first enzyme. While study of the bacterial immune system provides useful insights into immunology, the remainder of this article will focus on higher organisms' immune systems, particularly the human immune system. Contents showTocToggle("show","hide") 1 Recognizing self and non-s...

Growth curve

Figure 1: A "bi-phasic" bacterial growth curve. A growth curve in biology ...cell growth experiment . The observed pattern of bacterial growth is bi-phasic because two different sugars were present, glucose and lactose. The bacteria pre...

Genomics

...ea to Eubacteria . It has also been noticed that bacterial genes exist in eukaryotic nuclear genomes and that these genes generally encode mitochondrial and plastid proteins, giving support to the endosymbiotic theory of the origin of these organelles . Genetic similarity It is often stated th...

Gene therapy

... insulin, investigated introducing human genes to bacterial DNA. The modified bacteria then produce the corresponding protein, which can be harvested and injected in people who cannot produce it naturally. Scientists took the logical step of trying to introduce genes straight into human cells, focusing on ...

Flagellum

...e. The filament ends with a capping protein. The bacterial flagellum is driven by a rotary engine composed of... of protons (i.e., hydrogen ions ) across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species...

Fermentation

...s. Vinegar ( acetic acid ) is the direct result of bacterial fermentation. In milk, the acid coagulates the casein , producing curds. In pickling, the acid preserves the food from pathogenic and putrefactive bacteria. See also Industrial fermentation References Steinkraus, K. H., Ed. (1995). Han...

Bacterium

...ransformation (the transfer of naked DNA from one bacterial cell to another in solution, this can include dead...uction (the transfer of viral, bacterial, or both bacterial and viral DNA from one cell to another via bacteriophage) and; bacterial conjugation (the transfe...

Ethyl alcohol

...i , and many viruses , but is ineffective against bacterial spores . Because of this disinfectant property, alcoholic beverages can be stored for a long time. See also alcohol fuel alcoholic beverages biodiesel denatured alcohol methanol propyl alcohol External links Alcohol in A...

Endosymbiont

...celled algae, and several insect species contain bacterial endosymbionts. Many other examples of endosymbios...y mitochondria and chloroplasts , originated as bacterial endosymbionts. This theory is known as the endosymbiotic theory , confirmed and popularized by Ly...

Endosymbiont

...celled algae, and several insect species contain bacterial endosymbionts. Many other examples of endosymbios...y mitochondria and chloroplasts , originated as bacterial endosymbionts. This theory is known as the endosymbiotic theory , confirmed and popularized by Ly...

Disulfide bond

...ersible switch that turns a protein on or off when bacterial cells are exposed to oxidation reactions. Hydrogen peroxide ( H 2 O 2 ) in particular can severely damage DNA and kill the bacterium at low concentrations if it weren't for the protective action of the SS-bond. In rubber Disulfide bo...

Diabetes mellitus

...lu"), or an overwhelming new health problem (e.g., bacterial infection , myocardial infarction ). Insulin deficiency switches many aspects of metabolic balance in a catabolic direction. The liver becomes a net producer of glucose by way of gluconeogenesis and glycogenolysis . Fat in adipose tissue ...

Cilium

...y also be used to emphasize their differences from bacterial flagella. Cilia are found in all animals, although nematodes and arthropods only have non-motile cilia on some sensory nerve cells. Cilia are rare in plants occurring most notably in cycads . Protozoans ( ciliates ) possess motile cilia exclu...

Cell growth

... in other organisms. Non-eukaryotic cells such as bacterial cells reproduce by binary fission , a process that includes DNA replication, chromosome segregation, and cytokinesis. Eukaryotic cell reproduction either involves mitosis or a more complex process called meiosis . Mitosis and meiosis are sometim...

Brain

... affect the brain are caused by germs. Viral or bacterial infection of the meninges, the membrane that covers the brain, can lead to meningitis . Bovine spongiform encephalopathy is a deadly disease among cattle and is linked to prions . Some brain disorders are congenital . Tay-Sachs disease , ...

Full blood count

...clude: Neutrophil granulocytes - May indicate bacterial infection. Lymphocytes - Higher with some vir...c leukaemia CLL . Monocytes - May be raised in bacterial infection Eosinophil granulocytes - Increased in parasitic infections. Basophil granulocytes ...

BLAST

...that researchers use BLAST to answer are Which bacterial species have a protein that is related in lineage to a certain protein whose amino-acid sequence I know? Where does the DNA that I've just sequenced come from? What other genes encode proteins that exhibit structures or motifs such as the ...

Biophysics

...sts Howard Berg , characterized properties of bacterial chemotaxis Friedrich Dessauer , research on radiation, especially X-rays Walter Friedrich Boris Rajewsky Mikhail Volkenshtein , Revaz Dogonadze & Zurab Urushadze , authors of the Quantum-Mechanical (Physical) Model of Enzyme C...

Bacterium

...ransformation (the transfer of naked DNA from one bacterial cell to another in solution, this can include dead...uction (the transfer of viral, bacterial, or both bacterial and viral DNA from one cell to another via bacteriophage) and; bacterial conjugation (the transfe...

Bacterial conjugation

...cterial conjugation is the often regarded as the bacterial equivalent of sexual reproduction or mating ; ...ome (a plasmid that can integrate itself into the bacterial chromosome by genetic recombination ) of about 100 kb (kilo base pairs ) length. It carries its ...

Archaea

...s in molecular biology - do not show the typical bacterial features, but are extremely similar to those of eukaryotes . For instance, archaean translation uses eukaryotic initiation and elongation factors, and their transcription involves TATA-binding proteins and TFIIB as in eukaryotes. Several other cha...

Antigen

... metabolism , or because of viral or intracellular bacterial infection . The fragments are then presented on the cell surface in the complex with class I histocompatibility molecules . If cytotoxic CD8 + T cells recognize them, they begin to secrete different toxins that cause the lysis or apoptosis ...

Antibiotic

...ed interesting anti-bacterial effects from various bacterial secretions, the German scientist E. de Freudenreich in 1888 isolated a bacterial secretion and noted its antibacterial properties. Pyocyanase, secreted by Bacillus pyocyaneus, retar...

Ames test

...sted agent will be toxic enough to simply kill the bacterial culture in which case a "thin lawn" is observed. S-9 In some Ames assays an S-9 mix is added. The S-9 mix contains liver enzymes , generally from a rat. These enzymes can metabolize the agent being tested in order to predict the mutagenic prop...

Alexander Fleming

...nspected the Petri dish further and found that the bacterial colonies around the fungus were transparent because their cells were lysing . Lysis is the breakdown of cells, and in this case, potentially harmful bacteria. The importance was immediately recognized, however the discovery was still underestimate...