Amino acids

 Amino acids are the units of proteins. this molecule contains an alpha carbon which is the central carbon, in its four valencies it attaches with an amino group, a carboxyl group, a hydrogen group, and a R group. there are many amino acids but among them, 20 amino acids form all the proteins of living organisms.

depending on the R group the amino acids are classified into 5 groups ( in some cases they are classified into 4 groups). These groups are:

1) Nonpolar aliphatic: glycine, alanine, valine, leucine, isoleucine, methionine, proline

2) nonpolar aromatic: tryptophan, phenylalanine, tyrosine.

3) polar uncharged: serine, threonine, asparagine, glutamine, cysteine

4) polar positively charged: arginine, histidine, lysine

5) polar negatively charged: aspartate, glutamate

Some facts

> Amino acids have two isomeric forms: L-isomer and D-isomer. all living cells contain an L-isomeric form.

> All the amino acids that take part in the formation of ribosomal proteins have a S-configuration.

> Amino acids are also standard and non-standard amino acids ribosomal and non-ribosomal amino acids respectively.

> All the amino acids contain alpha carbon which is chiral in nature except for glycine.

> An amino acid during different pH conditions becomes positively charged negatively charged and uncharged. 

> Zwitter ion is the form of amino acid in which it becomes neutral (NH2 becomes NH3+ and COOH becomes COO-, so the net charge is 0), and the pH at which an amino acid remains in its zwitterion form is called the isoelectric point or pI.

This post contains a few facts about amino acids, hope you like this.

                                                                                      Thank you for reading. (  - Bio blog)

Popular posts from this blog

pbr322

Image
pbr322 is a plasmid vector. P stands for plasmid, B is for bolivar ar R is for Rodriguez. Contains an origin of replication, an ampicillin resistance and a tetracycline resistance gene. Contains 40 restriction sites, 11 of then are in tet resistance gene and 6 of them are in amp resistance gene. Others are present throughout the plasmid. Source of these genes are- Ori site - pMB1 plasmid amp resistance gene - rsf2124 Tet resistance gene - psc101 EcoR1 restriction site is denoted as 0 . HindIII restriction site is present on the promoter region of tet gene. Treated with this restriction enzyme, causes inactivation of tetracycline resistance. Rop gene is present which controls the copy number. hope this post will help (~Bio blog) Other posts http://bioblogsworld.blogspot.com/2022/07/enzyme-immobilization.html http://bioblogsworld.blogspot.com/2022/07/malolactic-fermentation.html https://bioblogsworld.blogspot.com/2022/12/corynebacterium-diphtheriae.html
Read more

Gram staining method

In this post i am going to describe gram staining method in brief. Introduction Gram staining procedure is a differential staining method used to differentiate between gram positive and gram negative bacteria. First used by Hans Christian Gram. Gram positive bacteria stains violet or dark blue. Gram negative bacteria stains red. Materials Crystal violet; used as a primary stain Safranin; used as a counter stain Grams iodine Glass slide Distilled water Decolorizer (ehtanol) Inoculating loop Procedure 1. Take the slide and wash it,dry it. 2. Take a drop on the slide. 3. Using inoculating loop take the bacterial sample and mix it in the water drop. 4. Make a smear of the water drop. 5. Air dry the smear. 6. Heat fix the smear. 7. Add crystal violet on the smear for 45sec to 1min. 8. Then add grams iodine(you can also wash the crystal violet with distilled water before adding iodine) and wait for 30 sec to 45 sec. 9.wash with decolorizer. 10. Add safranin. Wait for 45 sec to 1 min. 11. was...
Read more