Friday, August 26, 2011

A Biotechnological Advancement..

Bio-luminescent bacteria occur nearly everywhere, and probably most spectacularly as the rare "milky sea" phenomenon, particularly in the Indian Ocean where mariners report steaming for hours through a sea glowing with a soft white light as far as the eye can see.

Sea water bacteria of Genera Vibrio and Photomicrobium produce bioluminescence with the help of enzyme Luciferase. In the sea, bioluminescent light is concentrated in the blue window of greatest optical transparency of seawater. Most organisms emit between 440 nm and 479 nm (visible range of light). Some cnidarians have green fluorescent proteins that absorb an initially blue emission and emit it shifted towards the green (~505 nm). By using Recombinant DNA technology we can produce luciferase in vitro. The gene cassette responsible for the expression of Luciferase can be PCR (Polymerase Chain Reaction) amplified in vitro using primers specific for the gene. These primers possess restriction sites which can be cleaved by restriction enzymes and cloned in a suitable expression-based vector system. The vector system is a Plasmid - an extrachromosomal, self replicating DNA entity. The plasmid can be opened using the same restriction enzymes (as for the gene of interest - in this case, Luciferase) and could be ligated with the luciferase cassette. Once cloning is performed the plasmid can then be transformed into the host bacteria, which in this case would be E.coli (most commonly used as a host expression system). Growth of these recombinant bacteria allow expression of the desired enzyme which can be subsequently purified using differential gradient centrifugation and other biochemical techniques.

For those who are unfamiliar with the rDNA technology please refer to following: http://www.blackwellpublishing.com/allison/docs/sample_ch8.pdf


In a continuously aerated system this enzyme can produce light. This chemical reaction consumes oxygen - aerobic system is, thus, necessary. 


Empirical reaction:
FMNH2 + O2 + RCHO -----------> FMN + RCOOH + H2O + "LIGHT" 

Bacterial luciferin is a reduced riboflavin phosphate (FMNH2) which is oxidized (FMN) in association with a long-chain aldehyde, oxygen, and a luciferase enzyme.

Luciferase catalyzed reaction
The reaction is catalyzed by ‘luciferase’. The enzyme itself is never consumed in a reaction, it only catalyzes it. The mere presence of the protein molecule is sufficient enough to trigger the reaction. One enzyme molecule can be engaged only in one reaction at a time, however when carried out in sufficiently higher scale, it will produce light with greater intensity as a cumulative effect.

The enzyme, after the generation of light is free to participate in another such reaction. Thus the enzymes never deplete. However, they loose their functionality - denature - after  a while i.e., shelf life of the protein molecule. Thus, they need to be replaced if used in-vitro. When supply of raw material and aerated conditions are maintained the chemical reaction is triggered. This light, if amplified in a correct manner (using mirrors / bleach), will be an  alternative source of light. 

Kindly refer to our FAQ section on facebook page.


I, on behalf of Bio-Solutions, request all engineers / physicists, interested in making this project a success, to make suggestions here.


Objective - To have a different way of looking at sources of light for household usage
Vision - A brighter India, A better India.
Utility - Rural regions, roads and highways, coastal regions, rail-routes.  
Beneficiaries - Everyone.
Issues - 
  1. Success rate of rDNA cloning is relatively low. 
  2. Applicability in rural regions is a challenge.
  3. Cost effectiveness as compared to solar energy conservation methods - Solar Panels.
  4. Waste in the form of bio-mass disposal.
  5. Handling and awareness.