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Showing posts from March, 2013

Southern Blotting / Hybridisation!

Southern blotting is used for finding specific DNA sequence from a DNA sample by using the combination of techniques like  gel electrophoresis, capillary electrophoresis and hybridization. The DNA from the gel (after gel electrophoresis)is transferred to a nitrocellulose membrane and hybridization analysis is done for finding out the sequence of our interest using a probe) Let us discuss here the steps involved in doing Southern blotting. The steps are 1) Preparation of Sample 2) Restriction of the Sample 3) Gel Electrophoresis 4) Pre-treatment of the gel 5) Blotting 6) Hybridization 1) Preparation of Sample: (plant/animal/bacterial) For tissue or blood samples the DNA could be obtained by treating with SDS (Sodium dodecyl Sulphate) If we are going to have the DNA from a bacterial sample, there are separate protocols for extracting genomic DNA and pDNA . For extracting DNA from plants, CTAB (cetyltrimethyl ammonium bromide) is used. This CTAB binds with the DNA and helps

Plant Bio Reactors (PBR)

You might be aware of using E.coli for producing human proteins. E.coli is a well established expression system and easy to handle. And many people are working on this E.coli (even I'm handling only E.coli in my laboratory most times) Okay, we are fine with E.coli, and we are producing our protein of interest in that. And what is the need for an eukaryotic expression system? That thing, I explained in one of my previous posts ( Clone human genes into plants! ) I explained in that post like we are expressing our human proteins and we are growing the entire plant for obtaining our protein of interest. And we need not do that all time and there is a choice of growing plant cells in bio reactors! Yes, we do grow E.coli in bio reactors and why not the plant cells? You might be aware of this plant bio reactors and here I'm going to share something that I know about them.  Plant bio reactors I attended a seminar on "Advances in plant biotechnology" and as you g

Tuberculosis Diagnosis!

Hi, Today I'm going to share something about TB! TB - Tuberculosis is generally caused by Mycobacterium tuberculosis.  The most common symptom of TB is "non -stop" cough! They say, many people in India are "carrier" of the bacteria, but not the disease! Oh God! if you are in India, better go and check for this bacteria! The possibility of the spread of the disease could be due to unhygienic conditions! You spit in public places? you sneeze? cough? No problem, you can sneeze or cough, but be careful! Careful coughing? careful sneezing? yes, you might spread the population this mycobacterium you are carrying (you need not have TB), so, be careful in sneezing and coughing! Okay, let us come to the point, I started typing this with a view of giving an overview about "the diagnosis of Tuberculosis". The most common test used for checking TB is "Tuberculin Skin Test". Let me explain you how this is done! Tuberculin Skin Test! Let us firs