Friday, November 3, 2017

November 03, 2017 Friday

Bedtime Story 


The Three Papers of Francisco Mojica


There was a reason for my devoting bedtime stories of the last few nights to publication of a scientific paper.

In the coming nights as we enter the world of microbiology and genetics and more specifically CRISPR/Cas system, we will wade through many scientific papers most of them not even remotely glamorous as the four papers of Annus mirabilis.  

Yet papers need not necessarily be that sensational to have an impact on revelation of scientific truths, the only truth that is meaningful and which we apes can rely upon.
           
So let us see the papers that Francisco Mojica published.

The first paper that was published in 1993 by Mojica and his team was “Transcription at different salinities of Haloferax mediterranei sequences adjacent to partially modified Pstl sites” in Molecular Biology.

In this paper Mojica reported that the DNA fragment that he had investigated under the guidance of his advisor had an extremely curious nature – it was characterized with multiple copies of a near-perfect, roughly palindromic, repeated sequence of 30 bases, separated by spacers of roughly 36 bases.

This was very unique and a pattern that was unheard in microbial genomes.   

Mojica then was just 28 and was totally enthralled by these strange new repeating patterns occurring within DNA of some species of Archaea and decided to devote his life investigating it.

This man is a true scientist.

The second paper was published in 1995 in the same journal and was titled, “Long stretches of short tandem repeat are present in the largest replicons of the Archaea Haloferax mediterranei and Haloferax volcanii and could be involved in replicon partitioning.”

The title itself is complicated and needs some explanation.

If you note the title of his second paper, it has two components; the first is the mention of short tandem repeats and second is the tentative conclusion that they could be involved in replicon partitioning.

What Mojica was suggesting was that these clustered repeats had a role in correctly segregating replicated DNA into daughter cells during cell division.

Replicon is a genetic term that denotes that region of either DNA or RNA that replicates from a single origin.

As it turned out later this conclusion proved to be wrong.

Note mon ami that so far the term CRISPR has never been used in any publication.

It was only in 2001 that he and his co researcher Ruud Jansen proposed this specific term CRISPR – Clustered Regularly Interspaced Short Palindromic Repeats – for this clustered repeat that has now been found in twenty more species of microbes. 

Now that there was a name, it became an area of interest for many groups of researchers all over the world.

We shall continue with this story of these mysterious short tandem repeats in the nights to come.

Stay tuned to the voice of an average story storytelling chimpanzee or login at http://panarrans.blogspot.com
                              
Good night mon ami and my fellow cousin ape.
                           
  
                

             












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Another great educator and a teacher that I am aware of is Professor Subhashish Chattopadhyay in Bangalore, India.

While I narrate stories, Professor Subhashish an electronic engineer and a former professor at BARC, does and teaches real mathematics and physics.

He started the participation of Indian students at the International Physics Olympiad.

Do visit him here:


All his books can be downloaded for free through this link:


For edutainment and English education of your children, I recommend this large collection of Halloween Songs for Kids:



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