BIOLUMINESCENCE IN PLANTS

BIOLUMINESCENCE IN PLANTS

1. Sam Higginbottom University of Agriculture, Technology & Sciences, Prayagraj - 211007 (U.P) India An Assignment on BIOLUMINESCENCE IN PLANTS SUBMITTED BY: SUBMITTED TO ABHIMANYU KUMAR TOMAR DR DEENA WILSON 19MSHFS009 DEPARTMENT OF HORTICULTURE MSc Ag Horticulture Fruit Science 1

2. 2 S.NO TOPIC 1. DEFINITION 2. INTRODUCTION 3. SOME OF THE ANIMALS THAT MAKE LIGHT 4. HOW IT HAPPENS? 5. CHEMISTRY’S ROLE 6. REASEARCH DURING 2017 AT MIT 7. RECENT RESEARCH DATED 27 TH APRIL 2020

3. DEFINATION When a living organism produces and emits light as a result of chemical reaction is called Bioluminescence. 3

4. 2. INTRODUCTION Bio means “Living” in Greek while Lumen means “light” in Latin. During the process, chemical energy is converted into light energy. The process is caused by enzyme catalyzed chemo luminescence reaction. All bioluminescent organisms use a reaction between an enzyme and a substrate to make light, but different species use different chemicals in the process. 4

5. 3. SOME OF THE ANIMALS THAT MAKE LIGHT Many different types of animals Microscopic cells to fish and even few sharks. No higher vertebreates above the fish 5

6. Bacteria Radiolaria Dinoflagellates Funfi Coenlenterates and Ctenophores (Jelly Fish) 6

7. Gastropods: Squids, Octopus etc Annelids: Polychaetes, Earthworms Marine Crustaceans Insects: Beetles, Flies, Centipedes etc 7

8. Echinoderms: seastars , sealilies , bitterstars Tunicates: pyrosomes , larvaceans Sharks (rare) Fishes- many different typess 8

9. Dinofagellates are the most commonly encounted bioluminescent organism. It causes sparkling light. “Bioluminescent bays” which are tourist destinations in Puerto Rico and Jamaica Comb Jellies- 90% 9

10. 4. How it happens? Bioluminescence is product of a chemical reaction in organisms. Three ingredients are needed for bioluminescence to occur Luciferins : It is protein like light producing substance. Luciferase : It is enzyme and it allows the light producing chemical reaction to take place. Oxygen : It is colourless and odourless gas. Oxygen form 21% of Earth’s atmosphere and it is found in water. 10

11. In presence of Oxygen, the enzyme LUCIFERASE acts upon LUCIFERIN to produce energy. This energy takes the form of light. Luciferase allows oxygen to combine with luciferin and this reaction produces light and oxydized luciferin become inactive Oxy-luciferin. Some reaction do not involve this enzyme luciferase, so these reaction involve chemical called Photo-Protein that combine with oxygen and luciferase but require another agent, often an ion of element calcium, to produce light 11

12. 5. CHEMISTRY’S ROLE Bioluminescence is chemiluminescence that occurs in a living organism. In chemiluminescence, a molecule gets excited by an outer energy source and goes to a higher energy state than its usual ground state. When the molecule looses energy, it returns to its ground energy state, and emits a photon of light. In bioluminescence, the molecule that gets excited by an outside source is luciferin, and the outside source is the catalyst luciferase. 12

13. 6. RESEARCH DURING 2017 at MIT Imagine that instead of switching on a lamp when it gets dark, you could read by the light of a glowing plant on your desk. MIT engineers have taken a critical first step toward making that vision a reality. By embedding specialized nanoparticles into the leaves of a watercress plant, they induced the plants to give off dim light for nearly four hours. They believe that, with further optimization, such plants will one day be bright enough to illuminate a workspace. This technology could also be used to provide low-intensity indoor lighting, or to transform trees into self-powered streetlights, the researchers say. 13

14. NANOBIONIC PLANTS Plant nanobionics , a new research area which aims to give plants novel features by embedding them with different types of nanoparticles. The group’s goal is to engineer plants to take over many of the functions now performed by electrical devices. The researchers have previously designed plants that can  detect explosives  and communicate that information to a smartphone, as well as plants that can  monitor drought conditions . Lighting, which accounts for about 20 percent of worldwide energy consumption, seemed like a logical next target. To create their glowing plants, the MIT team turned to luciferase, the enzyme that gives fireflies their glow. Luciferase acts on a molecule called luciferin, causing it to emit light. Another molecule called co-enzyme A helps the process along by removing a reaction byproduct that can inhibit luciferase activity.  14

15. The MIT team packaged each of these three components into a different type of nanoparticle carrier. The nanoparticles, which are all made of materials that the U.S. Food and Drug Administration classifies as “generally regarded as safe,” help each component get to the right part of the plant. They also prevent the components from reaching concentrations that could be toxic to the plants. The researchers used silica nanoparticles about 10 nanometers in diameter to carry luciferase, and they used slightly larger particles of the polymers PLGA and chitosan to carry luciferin and coenzyme A, respectively. To get the particles into plant leaves, the researchers first suspended the particles in a solution. Plants were immersed in the solution and then exposed to high pressure, allowing the particles to enter the leaves through tiny pores called stomata. 15

16. Particles releasing luciferin and coenzyme A were designed to accumulate in the extracellular space of the mesophyll, an inner layer of the leaf, while the smaller particles carrying luciferase enter the cells that make up the mesophyll. The PLGA particles gradually release luciferin, which then enters the plant cells, where luciferase performs the chemical reaction that makes luciferin glow. The researchers’ early efforts at the start of the project yielded plants that could glow for about 45 minutes, which they have since improved to 3.5 hours. The light generated by one 10-centimeter watercress seedling is currently about one-thousandth of the amount needed to read by, but the researchers believe they can boost the light emitted, as well as the duration of light, by further optimizing the concentration and release rates of the components. 16

17. 7. RECENT RESEARCH DATED 27 TH APRIL 2020 Scientists have genetically engineered a plant with not just a visible glow, but a self-sustaining glow that lasts for the duration of the plant's life cycle. The team worked on two species of tobacco plant. And, unlike previous genetically engineered glowing plants, which used bioluminescent bacteria or firefly DNA, these plants were engineered using the DNA of bioluminescent fungi. The caffeic acid cycle, which is a metabolic pathway responsible for luminescence in fungi, was  recently characterised . Light emission was reported in  Nicotiana tabacum  and  Nicotiana benthamiana  plants without the addition of any exogenous substrate by engineering fungal bioluminescence genes into the plant nuclear genome. 17

18. It was discovered that these fungi synthesise luciferin from a compound called caffeic acid, worked upon by four enzymes. Two enzymes work to transform caffeic acid into a luminescent precursor; a third enzyme oxidises this precursor to produce a photon. The fourth enzyme then converts the molecule back to caffeic acid, which can be recycled through the same process. And this is where things get interesting - because  caffeic acid  (no relation to caffeine) is found in all plants. It's key to the biosynthesis of  lignin , the wood polymer that gives plant cell walls rigidity and strength. Caffeic acid is found in all plants. It's key to the biosynthesis of  lignin , the wood polymer that gives plant cell walls rigidity and strength. 18

19. The team reasoned that it might, therefore, be possible to genetically engineer plants to reallocate some of their caffeic acid to the biosynthesis of luciferin, as seen in  bioluminescent fungi . They spliced their tobacco plants with four fungus genes associated with bioluminescence, and carefully cultivated them. And they found that the plants glowed with a light visible to the naked eye from seedling to maturity - without any apparent cost to the health of the plant. 19

20. This suggests that, unlike expression of bacterial bioluminescence, expression of caffeic acid cycle is not toxic in plants and does not impose an obvious burden on plant growth, at least in the greenhouse. They found that younger parts of the plant glowed most brightly, with the flowers growing brightest of all. These produced, the researchers said, around a billion photons per minute. That's not nearly enough to read by, but it is bright enough to be clearly visible. 20

21. REFERENCES news.mit.edu askbiologist.asu,edu www.slideshare.net>bioluminescence-ppt 21