Proteins & Amino Acids | Biochemistry

Summary

This video explains proteins, one of the essential macromolecules. It describes the structure of amino acids, the building blocks of proteins, which consist of an amine group, a carboxyl group, and a unique functional group. The script explains how amino acids bond through dehydration to form polypeptides, which then fold into functional proteins due to interactions between their functional groups. These proteins are vital for numerous bodily functions, including acting as enzymes, receptors, and transporters. The video also touches on how mutations can alter protein function, affecting overall health.

Takeaways

• 🌟 Proteins are macromolecules composed of carbon, hydrogen, oxygen, and nitrogen.
• 🔍 The basic unit of proteins is the amino acid, which includes an amine group and a carboxyl group.
• 🌈 There are 20 different types of amino acids, some of which are essential and must be obtained through diet.
• 💧 Amino acids are linked together through a dehydration process to form polypeptides.
• 🔗 The sequence and type of amino acids determine the properties of the resulting protein.
• 🧬 The folding of a polypeptide chain is influenced by the interactions between its functional groups.
• 🌀 Hydrophobic and hydrophilic properties of amino acids affect how a protein folds and its interaction with water.
• 🔑 The three-dimensional structure of a protein, or its quaternary structure, is crucial for its function.
• 🧬 Mutations in DNA can lead to changes in amino acids, which can alter protein folding and function.
• 🏋️‍♂️ Proteins perform a wide range of functions in the body, including structural support, enzymatic activity, and transport.

Q & A

What atoms primarily make up proteins?

Proteins are primarily composed of carbon, hydrogen, oxygen, and nitrogen.

What is the basic subunit of proteins?

The basic subunit of proteins is the amino acid.

What are the three main components of an amino acid?

An amino acid consists of an amine group (nitrogen with two hydrogens), a carboxyl group (carbon with a double bond to oxygen and an OH group), and a functional group.

Why are some amino acids called essential amino acids?

Essential amino acids are those that the human body cannot produce and must be obtained through the diet.

How do amino acids differ from one another?

Amino acids differ based on their functional group, which gives them unique properties like being hydrophobic, hydrophilic, acidic, or basic.

What process links amino acids together to form a polypeptide chain?

Amino acids are linked together through a process called dehydration synthesis, where a water molecule (H2O) is removed to join them.

What determines the way a polypeptide folds into a functional protein?

The folding of a polypeptide into a functional protein is influenced by the interactions between the functional groups of the amino acids, such as charges and hydrophobic or hydrophilic properties.

What are some functions of proteins in the human body?

Proteins perform many functions, including acting as enzymes to speed up chemical reactions, transporting molecules, acting as receptors, and providing structure to cells and tissues.

What is a potential consequence of a mutation in a single amino acid?

A mutation in a single amino acid can change its properties (e.g., from acidic to basic), which can alter the folding and function of the protein, potentially leading to disorders or malfunction.

How many different types of proteins does the human body produce?

The human body produces between 20,000 to 50,000 different types of proteins.

Outlines

00:00

🔬 Understanding Proteins and Amino Acids

Dr. Mike introduces proteins as a macromolecule and explains their composition. Proteins, like carbohydrates and fats, contain carbon, hydrogen, and oxygen, but they also have nitrogen. Amino acids are the basic subunits or monomers of proteins, each composed of an amine group (nitrogen with two hydrogens), a carboxyl group (carbon with a double bond to oxygen and an OH group), and a functional group that differentiates them. There are 20 different amino acids, with some being essential (obtained from the diet) and others synthesized by the body. The functional group gives each amino acid unique properties, such as being hydrophobic or hydrophilic, acidic or basic, which plays a key role in their interactions.

05:02

🧬 The Formation of Polypeptides and Protein Folding

Amino acids connect to form polypeptides through a dehydration process where water is removed, linking them into a chain. This long chain of amino acids, known as a polypeptide, isn't yet a fully functional protein. The functional groups on each amino acid determine how the polypeptide folds. Positive and negative charges attract or repel, hydrophobic groups avoid water, and hydrophilic groups seek exposure to water. The folding process creates a 3D structure called a quaternary structure, which gives the protein its functional shape. This folding is crucial because any change in amino acid properties can alter the protein's function, as seen in mutations that affect DNA.

Keywords

💡Proteins

Proteins are a type of macromolecule composed of carbon, hydrogen, oxygen, and nitrogen. In the video, proteins are highlighted as essential molecules made from chains of amino acids, which fold into specific shapes to perform various functions in the body. Proteins are responsible for functions like enzymatic activity, transport, and structural support.

💡Amino Acids

Amino acids are the basic subunits, or monomers, of proteins. Each amino acid contains an amine group, a carboxyl group, and a unique functional group. The video explains that there are 20 different amino acids, and their different functional groups give them specific properties, such as hydrophobicity or acidity, which influence how proteins fold.

💡Polypeptide

A polypeptide is a chain of amino acids linked together through peptide bonds. As the video explains, polypeptides are formed through a dehydration process and eventually fold into proteins. Polypeptides are the precursor to functional proteins and must fold properly to perform biological tasks.

💡Dehydration Reaction

A dehydration reaction refers to the process by which water is removed during the formation of peptide bonds between amino acids. The video describes how one amino acid loses a hydroxyl group (OH) from the carboxyl group, and another amino acid loses a hydrogen (H) from its amine group, forming water (H2O) and linking the amino acids.

💡Functional Group

The functional group in an amino acid is the part that distinguishes one amino acid from another. These groups can have various properties, such as being hydrophobic, acidic, or basic. The video explains how these properties determine how the polypeptide folds, which affects the overall function of the protein.

💡Protein Folding

Protein folding is the process by which a polypeptide chain folds into its functional three-dimensional structure. In the video, it's explained that folding is driven by interactions between the functional groups of amino acids, such as positive and negative charges or hydrophilic and hydrophobic tendencies. Proper folding is crucial for a protein’s function.

💡Quaternary Structure

The quaternary structure of a protein refers to the three-dimensional arrangement of multiple polypeptide chains into a functional protein complex. The video mentions that proteins often reach their functional form at this level, where several polypeptides fold together, allowing them to perform essential biological functions.

💡Essential Amino Acids

Essential amino acids are those that the human body cannot synthesize and must be obtained through diet. The video points out that there are about 8 essential amino acids, and a deficiency in these can affect the body’s ability to produce certain proteins.

💡Hydrophobic and Hydrophilic

Hydrophobic means 'water-fearing,' and hydrophilic means 'water-loving.' In the video, these terms are used to describe how different amino acids react with water. Hydrophobic amino acids tend to hide from water by folding into the interior of the protein, while hydrophilic amino acids prefer to be on the outside, interacting with the aqueous environment.

💡Enzymes

Enzymes are proteins that act as biological catalysts, speeding up chemical reactions in the body. The video explains that enzymes are crucial for enabling reactions to occur millions of times faster than they would without them. Many proteins in the body function as enzymes, highlighting their importance in biological processes.

Highlights

Proteins, like carbohydrates and fats, are macromolecules made of carbon, hydrogen, and oxygen, but uniquely contain nitrogen.

The basic subunit of proteins is the amino acid, which consists of an amine group (nitrogen and two hydrogens), a carboxyl group (carbon with double-bonded oxygen and OAH), and a functional group.

The name 'amino acid' comes from the combination of an amine group and a carboxylic acid (carboxyl group).

There are 20 different amino acids, each with a distinct functional group that defines its unique properties and characteristics.

Some amino acids are hydrophobic (repel water), while others are hydrophilic (attract water); some can be acidic or basic, and some carry positive or negative charges.

Essential amino acids are those that the body cannot produce and must be obtained through the diet, while the body can synthesize non-essential amino acids.

Amino acids bond through dehydration synthesis, where a water molecule (H2O) is removed to form a peptide bond between the amine group of one amino acid and the carboxyl group of another.

A polypeptide is formed when multiple amino acids are linked together, creating a long chain that is the precursor to a functional protein.

The functional groups on the amino acids cause the polypeptide chain to fold, influenced by forces such as attraction and repulsion between charged groups, and hydrophobic and hydrophilic interactions.

Protein folding results in a three-dimensional quaternary structure, which gives the protein its specific function in the body.

There are around 20,000 to 50,000 proteins in the human body, and they are produced based on genetic material.

Proteins serve numerous roles in the body, including forming enzymes that accelerate chemical reactions, transporting substances, and acting as receptors for signaling molecules.

The three-dimensional structure of a protein is crucial for its function, and even a single amino acid change (e.g., due to a mutation) can significantly alter the protein's shape and functionality.

Mutations in DNA can affect the folding and function of proteins by changing one amino acid, which may result in diseases or dysfunctional biological processes.

Proteins are the most functionally diverse macromolecules in the body, with roles ranging from structural support to catalyzing reactions and transporting molecules.

Transcripts

I run dr. Mike here now let's look at

proteins which is another type of

macromolecule now as we've been going

through looking at carbs looking at fats

and now proteins I've told you what type

of atoms compose the majority of these

types of macromolecules when it comes to

proteins just like the others contains

carbon contains hydrogen contains oxygen

but one difference is that they contain

nitrogen okay now just like fats and

carbohydrates they're made up of basic

subunits or monomers and then they're

built up to what we call polymers or

bigger molecules in this case we're

looking at as the monomer the smallest

subunit is that of the amino acid so

that's where we're going to begin now an

amino acid is made up of an amine group

now the amine group is simply a nitrogen

with two hydrogen that's what's called

an amine then what we've got is on the

other end a carbon with a double bond

oxygen and OAH this is called a carboxyl

group you would have seen the carboxyl

group again in the fats and also in the

carbohydrates and together what you'll

find is carboxyl has also termed

carboxylic acid and this is where the

named amino acid comes comes from the

amino group or the amine group and the

carboxylic acid together is amino acid

now the third thing that an amino acid

has is this functional group this is

what makes an amino acid different so

every amino acid has this core structure

of the a main the carbon and the

carboxyl the difference is this

functional group on the end now there's

20 different types of amino acids now

the some that are called essential amino

acids these are amino acids a weak

cannot make we must get these from our

diet the rest we can there's about six

to eight of them the rest we can make

ourselves now this functional group on

the end this is the thing like I said

that makes them different some of these

functional groups have specific

characteristics or properties or

personalities that make them so

different for example some may be

hydrophobic that means they don't like

being near water some may be acidic

some may be basic some may be quite

positive some may be negative and some

may actually like water being close to

water called hydrophilic now this is

important because when we take an amino

acid and we click it together with

another amino acid which is what we're

doing here we're starting to create what

we call a polypeptide this is a polymer

this is a chain of amino acids so we

simply take one amino acid and another

amino acid and just like we spoke about

when we were clicking together monomers

or carbohydrates like glycerol for

example and when we're clicking together

fats we go through a process of

dehydration we need to remove a water

molecule and here you can see we take

the O H group here from the carboxyl end

of one amino acid and we take a hydrogen

from the amine side of another amino

acid together with taking away water h2o

and now we've clicked two amino acids

together and we continue to do this to

create a polypeptide now when we create

a nice long polypeptide chain which

you've got here we're starting to move

towards something that's resembling a

protein but not yet what you'll see is

we've got this nice long chain with all

these different functional groups now

it's the functional groups that alter

this nice long linear polypeptide and

tell it to fold in upon itself how does

this work okay if one of these

functional groups is positive and

another is negative they're going to

want to be close to each other okay so

they arrange themselves to be near each

other if both are positive then they'll

want to be away from each other and

they'll fold themselves so they are away

from each other you may have one that

likes water or a couple that like water

that means they're going to fold

themselves so they're exposed to the

liquid environment you have some that

hate water so it wants to imbed itself

deep within the protein you're going to

some have some acid than some bases and

this also is going to alter the way that

it folds itself and what ultimately

happened it happens is you get this

three-dimensional what we call a

quaternary structure of a folded

polypeptide or group of polypeptides

into something called a protein and now

this folded protein is what actually has

the function in our body there's around

about 20,000 to 50,000 protein

means that our body makes okay from our

genetic material and when you're looking

at me right now you're basically looking

at all my proteins so it makes up the

majority of my skin and my eyes it has

all the functions in the body it they

basically make ends are or they are

enzymes so this makes reactions happen

millions of times faster than they would

without enzymes they shuttle things by

picking things up and taking them

elsewhere they can be receptors they can

bind to other things proteins have all

the function in the body so they're

extremely important and it's these

functional groups that fold it into its

functional property and if you have a

problem with it it could even just be a

single amino acid it could change this

one from an acid to a base that changes

the way it folds that alters the

function of the protein this is one way

that mutations in our DNA can affect our

proteins functions so this is proteins

as a macro molecule