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Project Violet Exploration: The Species & Molecules

Come investigate the many elements of Project Violet!

The Species and Molecules of Project Violet

Each of these species fight predators and need defense mechanisms, and therefore produce a drug-like molecule. We can harness this drug fighting ability to create drugs that can be used to fight rare cancers and other rare diseases in people. This list of species/molecules is not comprehensive (as there are actually hundreds!), but it gives a sample of just some of the species that are potential research candidates.

Horseshoe crab
HIV-1 virus
E. coli bacteria
Cone snails
Humans (we make knottins too!)

In the right-hand column we have taken just a few of these species to show more details about them and why they might be good research candidates. In order to view each of these molecules in 3D and to obtain more information on them, please click the species/molecule photos for each of the species in the right-hand column.

*The information in this section was obtained from Dr. Jim Olson's lab, RCSB Protein Data Bank, and a variety of plant/animal sources on the web. The protein images were created using Cn3D.

Scorpion - 1CHL

                                                                                                                                                       (click here)



The Deathstalker Scorpion makes Chlorotoxin (1CHL in PDB) as part of its venom. It is just one of the molecules that make up the scorpion's venom, and by itself it doesn't seem to have any toxicity in humans. Chlorotoxin gets past the blood-brain barrier into the brains of prey or predators. Our team turned Chlorotoxin into a drug to light up brain tumors during surgery.


- Scientific name: Leiurus quinquestriatus
- Also known as Egyptian Scorpions or Deathstalkers
- Found in the arid and hyper-arid regions of Northeastern Africa and the Middle East
- Length range is 80 to 110 mm
- Weight range is 1.0 to 2.5 grams
- Yellowish with brown spots
- Has three to six pairs of eyes, but bad vision
- Glows under ultraviolet light (hence the blue color in the picture)
- Can survive being in a freezer overnight

                                                                                                                                                                               [Photo credit:  Kenton Elliott]

Potato - 1H20

                                                                                                                                                      (click here)



Potatoes are big balls of starch under the ground: very appealing to grubs and worms. The Potato Carboxypeptidase Inhibitor (PCI) (1H20 in PDB) they make in their skin keeps them from being eaten by inhibiting animal enzymes that break down proteins. It is the PCI defense mechanism that has drug-like properties for the potato and potentially more.


- Scientific name: Solanum tuberosum
- Originated in the region of southern Peru
- First domesticated between 3000 BC and 2000 BC
- Important part of the world's diet: considered the fourth most important crop behind corn, wheat, rice
- Contains a variety of vitamins and minerals
- The word potato comes from the Spanish word patata
- Potato plants are usually pollinated by insects such as bumblebees
- There are around 5000 potato varieties in the world
- Largest recorded was 18 pounds and 4 ounces 

Spider - 2ROO

                                                                                                                                                       (click here)



The macrothele spider creates a venom to paralyze their insect prey. This venom contains a protein called Magi4 (2ROO in PDB) that is the key component that causes the paralysis. With some tweaking, perhaps this protein can 'kill' tumors and other diseases.


- Scientific name: Macrothele gigas
- Also known as 'funnel-web' or 'tube-web' spiders because of the shape of their webs represent funnels/tubes
- Found in a range of places including the western Mediterranean, West Africa, SE Asia, China
- Females can grow a body as large as 3cm
- Males are smaller, sometimes only half the size

                                                                                                                                                               [Photo Credit:]

Horseshoe crab - 1CIX

                                                                                                                                                      (click here)



The horseshoe crab makes the peptide Tachystatin A (1CIX in PDB); this is an 'antimicrobial' which acts as a defense mechanism against bacteria, viruses, and fungi.


- Scientific name: Tachypleus tridentatus
- Found in southeast Asia.
- Length ranges from 8 inches to 24 inches long, and weight ranges from 2.2 lbs to 9.9 lbs
- Average lifespan is 20-40 years
- Has ten eyes and can see UV light
- Has five pairs of legs
- Favorite food is worms
- Often called "living fossils" because fossils of their ancestors date back almost 450 million years
   (200 million years before dinosaurs existed!)
- Blood protects them from infection
- Long thin tail is used for changing directions while swimming

Petunia - 1N4N

                                                                                                                                                   (click here)



The petunia makes proteins that stop infections before they even start. The floral defensin-like protein (1N4N in PDB) molecule develops in the early stages of the flower's development. It accumulates in the outermost cell layers of petals, sepals, anthers, and styles, consistent with a role in protection of the reproductive organs.


- Scientific name: Petunia x hybrida
- Height is 6-18 inches
- Colors range from shades between white and red, purple, and yellow
- Closely related to potatoes, chili peppers, tobacco, tomatoes
- Has South American origins
- Name comes from the Brazilian word petun, which means "tobacco"
- Common garden petunias are edible and taste mildly sweet and spicy
- Attract hummingbirds and moths

                                                                                                                                             [Photo credit:]