The Isolation of Genomic DNA from the bacterium, Escherichia coli is explained in this section Aim of the experiment: To isolate the genomic DNA from Escherichia coli DH5α cells. PRINCIPLE OF THE EXPERIMENT The isolation and purification of DNA from cells is one of the most common procedures in contemporary molecular biology and embodies a transition […]
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Biotechnology, Molecular Microbiology
Level of disease The amount of a particular disease that is usually present in a community is referred to as the baseline or endemic level of the disease. This level is not necessarily the desired level, which may in fact be zero, but rather is the observed level. In the absence of intervention and assuming
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Epidemiology
Desoxycholate Citrate Agar (DCA) is a selective medium for the isolation of Salmonella and Shigella organisms. It is ideal for the investigation of pathogenic Enterobacteria. The Gram-positive organisms are totally inhibited by the sodium citrate and sodium desoxycholate in the medium. Proteus and coliforms are also highly inhibited. Salmonella typhi, S. paratyphi and Shigella species
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Culture media
In the previous section on DEPARAFFINIZATION PRIOR TO IMMUNOHISTOCHEMISTRY STAINING, we looked at deparaffinization and rehydration of paraffin-embedded tissue. In this section, we look at epitope unmasking protocol. Deparaffinization is an important process in the immunohistochemistry staining process; and it must be done prior to immunohistochemistry, especially for paraffin-embedded tissue samples. Deparaffinization is simply defined
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Immunology & Immune System
We have looked at deparaffinization and rehydration of paraffin-embedded tissue, as well as antigen-retrieval protocol and permeabilization and blocking non-specific binding on the sectioned tissue sample on the slide. In this section, we look briefly on antibody selection and antibody staining for immunohistochemistry. The selection of antibody for immunohistochemistry analysis is important for the overall
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Immunology & Immune System
Adenoviruses are found in the viral family known as Adenoviridae. They are non-enveloped viruses with an icosahedral nucleocapsid. Adenoviruses are DNA viruses; and they possess a double stranded DNA molecule. Adenoviruses are a group of viruses that typically cause respiratory illnesses, such as a common cold, conjunctivitis, croup, bronchitis, or pneumonia. In children, adenoviruses usually
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Virology
The production of beta-lactamase enzymes by Gram negative bacteria including E. coli, P. aeruginosa and Klebsiella species is an important mechanism by which the organisms evade both in vivo and in vitro antimicrobial onslaught. Beta-lactamase production by resistant test isolates can be evaluated for beta-lactamase production using the Nitrocefin test sticks (Oxoid, UK). The nitrocefin
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Antibiotic Resistance / Antimicrobial Resistance (AMR), Pharmaceutical Microbiology
Trypan blue is defined as a dye or stain that enables us to distinguish between living and dead cells. The trypan blue dye passes through the cell membrane of the dead cells; and this allows the dead cell to take up the colour of the dye. This way, the dead cells appear blue under the
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Microbe Lab, Techniques in Microbiology Lab
When phenol or a mixture of phenol:chloroform is mixed with a cell Lysate, two phases form: an aqueous and an organic phase. The polar DNA partitions into the polar or “aqueous phase”, and denatured proteins and other cellular debris partition into the organic phase. Salts are thought to dehydrate proteins, causing them to become less
WAYS TO SEPARATE DNA FROM OTHER CELLULAR MATERIALS: BINDING AND WASHING Read More »
Biotechnology, Molecular Microbiology
Enterococcus (plural: Enterococci) is a group of bacteria that is normally found in the intestines of humans and many animals. Two species of Enterococci, which are found in the body of healthy individuals, are Enterococcus faecalis and Enterococcus faecium. Both E. faecalis and E. faecium are associated with human diseases; and they are mostly involved
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Antibiotic Resistance / Antimicrobial Resistance (AMR), Pharmaceutical Microbiology