#protein enzymes

[hellsitegenetics]

How do you feel about aminoacyl-tRNA synthetase enzyme?

HOIUUOOUUOOUOHHH IM CATALYZING!!!!!!!!!!!!!!!!!!!!

[consult-sherlockholmes]

Can you explain to me the chemistry behind the denaturation of enzymes and the process of allosteric and competitive inhibition?

First of all it's important to understand what an enzyme is. An enzyme is a protein, that catalyses reactions after binding to a substrate and then converts it or splits it. An enzyme has a very specific shape so it can bind to the substrate, it's like a key and a lock. The substrate binds to the binding site, and in the catalytic or active centre the reaction takes place.

This is important to understand denaturation: Proteins are made out of amino acids that are bound with peptide bonds. Proteins have several levels of structure: Their primary level is the sequence of amino acids, the secondary structures are folded structures due to interactions of the peptide backbones via hydrogen bonds, like alpha helices or beta sheets. The tertiary structure is folding of the peptides due to electrochemical interactions between different amino acids. Amino acids can have different charges due to their side chains, they can be positive, negative or neutral charged. So those charges will either attract or repel each other, putting the peptide chain in a certain three dimensional shape or conformation. In the quaternary structure several peptide chains come together to create a bigger functional unit (the enzyme) made out of subunits, they often also interact with ions (cofactors) as their catalytic centre where the catalysed reaction takes place. All those levels create the specific shape of the enzyme that is required to bind to their target substrate. So if those structures are changed in any way, it won't work anymore because it can't bind. Just reading it probably makes it difficult to understand, so here's a textbook graphic.

This shape can be changed by denaturation. A protein can be denaturated by heat, or changed pH or high salinity and other not optimal conditions. During those conditions like changed pH the interactions between the molecules and side chains do not work anymore because pH can change the charges of the sidechains, so secondary, tertiary and quarternary structures will be changed. When those structures are changed the binding site will change too and not resemble the lock anymore where the key substrate can bind, so now the enzyme is inactivated/inhibited.

Enzymes can also be inhibited (or activated) by regulatory molecules binding to the enzyme, inhibitors or activators. This can be a competitive inhibition, when the inhibitor binds at the same binding and active site and blocking it, making the actual substrate that should be processed unable to bind there. Like a lock that already has a key stuck in it, you can't put another key in there. Allosteric inhibition is when the inhibitor binds at another site, not directly at the active site where the substrate binds. But by binding to the allosteric site the conformation of the enzyme gets changed by chemical interactions, changing the binding site so the substrate doesn't get recognised anymore. A key can't be insterted into a lock that has been changed.

Inhibtion can be irreversible (making the enzyme dysfuntional for the rest of it's existence until it is degraded) or reversible.

[carnivalcarriondiscarded]

Ayo come get your Howdy soup while it’s…uncomfortably warm and acidic

prolongedslurpingsound.wav

[ladysqueakinpip]

the only thing my sister and i have to offer to the rise fandom is theories about how lou jitsu's dna recombined with the turtles

[materialsscienceandengineering]

Wearable, printable, shapeable sensors detect pathogens and toxins in the environment

Researchers at Tufts University School of Engineering have developed a way to detect bacteria, toxins, and dangerous chemicals in our environment using a biopolymer sensor that can be printed like ink on a wide range of materials, including wearable items such as gloves, masks, or everyday clothing.

Using an enzyme similar to that found in fireflies, the sensor glows when it detects these otherwise invisible threats. The new technology is described in the journal Advanced Materials.

The biopolymer sensor, which is based on computationally designed proteins and silk fibroin extracted from the cocoons of the silk moth Bombyx Mori, can be embedded in films, sponges, filters, or molded like plastic to sample and detect airborne and waterborne dangers, or signal infections or even cancer in our bodies.

The researchers demonstrated how the sensor emits light within minutes as it detects the SARS-CoV-2 virus that causes COVID, anti-hepatitis B virus antibodies, the food-borne toxin botulinum neurotoxin B, or human epidermal growth factor receptor 2 (HER2), an indicator of the presence of breast cancer.

Read more.

[loverofallthingssmart]

not to be a stem nerd on main but like something about science makes me feel really good about myself. like being into science has actually increased my confidence. ik its not everyone’s cup of tea but WAH what a dear thing to me..

[butchlifeguard]

shes so right about everything ever

[ID: a screenshot of aoi asahina from danganronpa, saying "guess what i found! a pool! there's a pool here! a POOL! pool pool pool!" end ID.]

[exaltior-a]

Crazy how every single homestuck kid and troll with the minor exclusions of June, Rose, Jane and Equius have the potential to be lactose intolerant

[covenawhite66]

Updated research on small cellular machine called TRiC controls the folding of tubulin, a human protein that is the foundation of microtubules.

This challenges the previous understanding that TRiC and other machines like it, known as chaperonins, only passively create a favorable environment for folding but do not actively take part in it.

Many of the proteins that fold with the aid of TRiC are intimately linked to human diseases, including certain cancers and neurodegenerative disorders like Parkinson’s, Huntington’s, and Alzheimer’s diseases.

[pinkbat5]

the human enzyme galactokinase

[kemetic-dreams]

Did you know? Drinking snake venom will do nothing but… 🐍💦

Drinking snake venom will do nothing, because snake venom is a type of protein, when it enters the stomach it will be broken down into protease and peptone by proteolytic enzymes into the last amino acid!

But if there is a wound in the mouth, esophagus or stomach, it's "game over".

Because then it can mix directly with the blood, through the capillary.

Don't do this. It can be very deadly!

[ancientarchitectureenjoyer]

biochemistry is NOT for the weak🙏