CHAPTER 13

Perilous Proteins

PART 1 Proteins in Nature

We’ve noted throughout this health center that protein is the material of life, and that description is not limited to human life. Parts 1 – 4 of this Protein Health Center provide a look at a few of the more striking roles — and a few threatening results — of proteins in nature. READ MORE

Tough as Nails

Fingernails and toenails, the toughest areas of the body’s outmost layer, are made from sheets of protein. Nails are rigid and resilient due to keratin, a protein also found in skin and hair.

Sturdy fingernails serve the primary function of protecting vulnerable fingertips from injury and are also built-in tools for digging, scratching, and executing fine motor-skill jobs like untying a knot.

Clear nail polish, too, contains protein that can strengthen a brittle nail. These products are often marketed as “protein-enriched” or having a “protein base coat.” LESS

PART 2 Critter Protein

Research Report

Nature Knows Best

Much as we need protein as a composite material in the construction of bone and teeth, insects such as beetles, cockroaches, and ants depend on protein to build and sclerotize (harden) the layers of their outer shells. When they crunch under your foot, those are sheets of converted protein giving way. READ MORE

Insects require protein for numerous processes of their little lives. In fact, you’ve probably been the unwitting source of protein for at least one insect: A female mosquito extracts blood to obtain the protein needed to nourish her eggs.

While we’re at it, have you ever wondered why moth larvae bore holes in wool clothes and rugs? They seek the protein in the wool. Remember that wool is made from sheep’s hair. The larvae of clothes moths and carpet beetles don’t care whether or not it’s growing on the back of a living animal, they just seek the hair for its enriching protein meal. LESS

PART 3 Neurotoxic Threats

There are four types of snake venom, and all are complex mixtures of proteins. Venom has an analog in human saliva; in fact, the venom is the snake’s saliva. But snake venom is neurotoxic, meaning that its potentially devastating effects — shooting pain, convulsions, organ shutdown, paralysis — are wrought through the victim’s nervous system. The neurotoxins do their damage to nerve cells by binding to membrane proteins (proteins attached to the membranes of cells). READ MORE

Tetrodotoxin is the singularly potent neurotoxin carried by pufferfish (and a few related species), and there’s enough of it in one tennis-ball sized fish to kill 20 people. People would have little chance of exposure if they didn’t consume raw pufferfish, or fugu, as a delicacy. An experienced sushi chef must assiduously remove parts of the fish containing the neurotoxin. A poorly executed sushi surgery will result in big trouble for the adventuresome diner as there is no antidote. LESS

PART 4 Bad Trip: A Malevolent Mushroom

Of the 50-plus species of mushrooms that are poisonous, the death cap mushroom trumps all. The poison in a single death cap, which resembles the innocuous straw mushroom, can kill when consumed. The deadly toxin at work in this toadstool is amanitin, a polypeptide composed of eight amino acids. In the body of the hapless mushroom muncher, amanitin binds to an RNA enzyme causing liver cells to burst and protein production to grind to a halt.

theVisualMD Wishes to Thank our Scientific Collaborators:

Julie M. Jones, PhD, CNS., LN.
College of St. Catherine

David L. Katz, MD, MPH, FACPM, FACP
Yale University School of Medicine

Molly Morgan, RD, CDN, CSSD
Nutritionist, Creative Nutrition Solutions

Michael Stein, MD
Brown University