תכונותיהן של החומצות האמיניות

1. תכונותיהן של החומצותהאמיניות חומצותאמיניות הידרופוביות Alanine Valine A, Ala, alanine Phenylalanine Proline Methionine Leucine Isoleucine עתה סומן חלקה של חומצת האמינו שמשותף לכל הסוגים יחודו שלהאלניןהוא הקבוצההמתיליתשמקנה למולקולה אופיהידרופובי אלנין מתיונין ואלין לאוצין לבסוף, אינכם צריכים לזכור את הפרטים לגבי כל חומצתאמינואלא לדעת על סמך נוסחאות המבנה, שינתנו לכם, מהן התכונות של כל אחת מחומצות האמינו. פנילאלנין איזולאוצין פרולין

2. חומצותאמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות V, Val, valine Valine has two methyl groups so it's somewhat larger, rather more hydrophobic. So here we have valine.

3. חומצותאמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות F, Phe, phenylalanine This has this benzene ring, this unsubstituted benzene ring, very hydrophobic And we have phenylalanine.

4. חומצות אמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות P, Pro, proline Here's proline. Proline is a little different because it folds back onto the main chain of the amino acid. So, strictly speaking, proline is an imino acid instead of an amino acid but most biochemists don't make that distinction. So proline has all of these CH2's, so it's very hydrophobic and it links back to the nitrogen of the amino group of the amino acid.

5. חומצות אמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות M, Met, methionine methionine has a sulfur in here. It's one of two amino acids with a sulfur, and again it's very hydrophobic Methionine,

6. חומצות אמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות L, Leu, leucine And then we have leucine and isoleucine. Here's leucine, lot's of CH's, CH3's.

7. חומצות אמיניות הידרופוביות Alanine Valine PhenylalanineProline Methionine Leucine Isoleucine תכונותיהן של החומצותהאמיניות I, Ile, isoleucine lots of CH2's and CH3's. So those are the hydrophobicamino acids. Isoleucine is almost the same,

8. תכונותיהן של החומצותהאמיניות חומצות אמיניותטעונות Aspartic acid (aspartate) Glutamic acid (glutamate) Lysine Arginine Histidine D, Asp, aspartate it just has a CH2 and a carboxyl group, and so that's an example of an acidic group. aspartate, glutamate, lysine, arginine, histidine. chargedamino acids; Then we have the So aspartate is the simplest,

9. חומצות אמיניות טעונות Aspartic acid (aspartate) Glutamic acid (glutamate) Lysine, Arginine, Histidine תכונותיהן של החומצותהאמיניות E, Glu, glutamate Glutamate has basically the same thing, but with an extra CH2 in it. See there are two CH2's and a carboxyl group

10. Chinese restaurant syndromeתסמונת המסעדה הסינית MSG (monosodium glutamate) is abused as a flavor enhancer in some restaurants, including some Chinese restaurants. People who are sensitive to MSG get a sensation like a clamp placed over their head and tightened. Fortunately, the sensation is temporary. MSG (מונוסודיום גלוטמט) משמש להוספת טעם במסעדות מסוימות. בעיקר הוא נפוץ במסעדות סיניות. ישנם אנשים הרגישים לחומר זה ובעת האכילה נתקפים ברגישות המתבטאת בלחץ גדול בראשם שהולך וגדל. למזלם כאב הראש הוא זמני. זהו מלחנתרנישל החומצההאמיניתח. גלוטמית, מונומר הנמצא כמרכיב כמעט בכל החלבונים.

11. Charged amino acids Aspartic acid (aspartate) Glutamic acid (glutamate) Lysine, Arginine, Histidine תכונותיהן של החומצותהאמיניות K, Lys, lysine this has a nitrogen forming this amino group at the end which is the basic group and This is lysine the basic one, this hydrocarbon chain

12. Charged amino acids Aspartic acid (aspartate) Glutamic acid (glutamate) Lysine, Arginine, Histidine תכונותיהן של החומצותהאמיניות R, Arg, arginine Arginine has these three nitrogens and here we can have a charge on this Here's arginine. guanidino group up here, so that's another basicresidue.

13. Charged amino acids Aspartic acid (aspartate) Glutamic acid (glutamate) Lysine, Arginine, Histidine תכונותיהן של החומצותהאמיניות H, His, histidine And then we have histidine. Histidine is very interesting because its pK is very close to the pH in the body, and so the charge on this nitrogen here can be positive or negative depending on a variety of circumstances. And so this is a residue you often find at active sites of enzymes.

14. תכונותיהן של החומצותהאמיניות Polaramino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan S, ser, serine Polar means that they interact well with water, so it's the opposite of hydrophobic. So these are ones which have groups on them which will form hydrogen bonds and interact well with water. So this is the list: Serine has a hydroxyl group. It's very simple just a methyleneand a hydroxyl group serine, threonine, tyrosine, cysteine, asparagine, glutamine, tryptophan. Let's move onto the polaramino acids.

15. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות T, Thr, threonine Then threonine has a methyl group in addition.

16. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות Y, Tyr, tyrosine Tyrosine is a little more complex, it has the benzene ring but it only has this hydroxyl group out here making it polar.

17. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות C, Cys, cysteine Cysteine is the other amino acid with a sulfur in it, and you can see it again is very simple with that sulfur present. And if we move onto cysteine.

18. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות N, Asn, asparagine this carbonyl and amine group here. This group does not ionize, so it is not charged. It is not acidic; it's not basic. It doesn't ionize in the body. It's polar because it interacts well with water, but it's not ionized. And then we have asparagine. This again has a single CH2 group and now it has

19. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות Q, Glu, glutamine Same thing goes for glutamine. Glutamine just has an additional CH2 group and again it has this polar group at the end.

20. Polar amino acids Serine Threonine Tyrosine Cysteine Asparagine Glutamine Tryptophan תכונותיהן של החומצותהאמיניות W, Trp, tryptophan People usually put tryptophan in the group of polar amino acids, but personally I don't really agree with that. It has this nitrogen here which can form hydrogen bonds which gives it some polar character, but in practice the non- polar nature of these fused rings here actually is the dominant feature. So although tryptophan is often put in this group, it really has a mixture, as some of the others do, of properties. So finally, the last one on here is tryptophan.

21. תכונותיהן של החומצותהאמיניות Glycine G, Gly, glycine is just a hydrogen atom. So this is basically just a very quick run-through of the amino acids, and as we talk about them more and see how they're used, you'll get more familiar with them and see how they work and see how their different properties are important. Today what I really wanted to get across was the nature of the forces between amino acids and the properties of the amino acids, which are important. the simplest one of all, which I kept until last, And then there's glycine,