The Amazing and Practical Uses of Hagfish Slime

Hagfish slime is a gelatinous, protein-based substance secreted by hagfish in response to a threat. This gooey material has a surprising number of uses, and its unique properties may influence the future design of everything from clothing to missile defense. Key Takeaways: Hagfish Slime Hagfish slime is a protein-based, jelly-like substance emitted by hagfish as protection against predators.The slime is made up of strands that are stronger than nylon, thinner than human hair, and very flexible.  Because of these unusual properties, hagfish slime is used to produce durable, environmentally-friendly fabric. The slime has many other potential uses, which are being researched. Meet the Hagfish The hagfish is a slime-producing marine fish known for its lack of eyes and eel-like appearance. However, despite being nicknamed slime eels, these unique creatures arent eels at all. Rather, the hagfish is  jawless fish that possesses a skull, but no vertebral column. Its body is made up entirely of cartilage, like human ears and noses or the body of a shark. Because hagfish do not have skeletal systems, they can tie their bodies into knots. They often perform this feat while eating to increase the strength of their bite, and emitting slime to prevent the substance from choking them. Hagfish don’t have jaws, but they  do have two rows of â€Å"teeth† made of keratin, the same fibrous protein that  makes up the hair, hooves, and horns of other animals. They are scavengers that feed  on marine invertebrates and the carcasses  of marine life found on the seafloor. They dont have to rely on their teeth, either – theyre capable of absorbing nutrients through their bodies, and they can survive for months without eating. Hagfish are an important part of the marine ecosystem, and the slimy sea-dwellers are considered a delicacy in Korea. There is even a National Hagfish Day (the third Wednesday in October)  to celebrate the contributions of this unusual scavenger. The Characteristics of Hagfish Slime When a hagfish feels threatened, it releases  hagfish slime, a  protein-based, jelly-like substance  from  slime pores that run the length of its body. The slime is a thick glycoprotein excretion called mucin, which is the primary substance in mucus, commonly referred to as snot or phlegm. Unlike other types of mucus, however, hagfish slime doesn’t dry out.   The mucin is made up of  long, thread-like fibers, similar to  spider silk. These strands, which are arranged in bundles called skeins, are thinner than human hair, stronger than nylon, and extremely flexible.  When the skeins come into contact with seawater, the glue holding them together dissolves, allowing the slime to expand rapidly. It is said that one hagfish can fill a five-gallon bucket with slime in only a few minutes.  The slime  fills  the mouth and gills of  the hagfish’s  attacker, allowing  the hagfish  to escape. If a hagfish gets trapped in its own slime, it removes the gooey mess by tying its body into a knot. It then works the knot down the length of its body, pushing the slime off the end.   The Uses of Hagfish Slime Because of the strength, flexibility, and rapid expansion of hagfish slime, scientists are very interested in its potential uses. Researchers are experimenting with methods of creating man-made slime, since extracting the substance directly from hagfish is expensive and  stressful for  the animal. There are many possible  applications for hagfish slime. Hagfish are already used for making products such as â€Å"eel-skin† bags. The  strong, flexible fabrics made from hagfish slime could replace petroleum-based materials like nylon; the resulting fabric would be more durable and environmentally-friendly. Hagfish slime could be used in protective gear such as safety helmets and Kevlar vests. In the auto industry, hagfish slime could be used in airbags or to add lightweight strength and flexibility to car parts. Scientists think they may be able to use hagfish slime to create hydrogels that could be used in disposable diapers and farm irrigation systems. The U.S. Navy is currently working with hagfish slime in hopes of creating a substance that can protect divers from underwater attacks, fight fires, and even  stop missiles. Other  applications for hagfish slime include  tissue engineering and  replacing damaged tendons. Sources Bernards,  Mark A. et al. Spontaneous Unraveling Of Hagfish Slime Thread Skeins Is Mediated By A Seawater-Soluble Protein Adhesive.  Journal Of Experimental Biology, vol 217, no. 8, 2014, pp. 1263-1268.  The Company Of Biologists, doi:10.1242/jeb.096909.Mapp, Katherine. US Navy Synthetically Recreates Biomaterial To Assist Military Personnel.  Navy.Mil, 2017, http://www.navy.mil/submit/display.asp?story_id98521.Pacific Hagfish. Aquarium of the Pacific. http://www.aquariumofpacific.org/onlinelearningcenter/species/pacific_hagfish.Winegard, Timothy et al. Coiling And Maturation Of A High-Performance Fibre In Hagfish Slime Gland Thread Cells.  Nature Communications, vol 5, 2014.  Springer Nature, doi:10.1038/ncomms4534.