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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-confi...
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Corynebacterium diphtheriae

Corynebacterium diphtheriae C. diphtheriae is an aerobic gram-positive rod-shaped non-spore forming bacteria. here we are going to discuss some of the features of this bacteria. CHARACTERISTICS >As previously stated its a gram-positive rod >aerobic > non-spore forming >swelling near the pole giving it club like structure >contains granules that can be stained >no perfect branching is seen under a microscope >destroy epithelial cells and form pseudomembrane on the throat, larynx, and pharynx region  COLONY CHARACTERISTICS    greyish color colonies grow on blood agar, the colonies are granular with an uneven edge with little hemolysis. on Tinsdale medium brown or black color, colonies grow due to potassium tellurite. STAINING aniline dyes are used to stain the granules. PATHOGENESIS generally, these bacteria are harmless but upon infection with a lysogenic beta phage, these bacteria converted to toxigenic bacteria.  the gene responsible for toxin p...
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pbr322

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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
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Malolactic fermentation

Malolactic fermentation is an important step in wine making. This step occurs after primary fermentation. Malic acid which is present during wine making procedure, converted to lactic acid during this malolactic fermentation. Microbial culture used  Leuconostoc sp. & Some other lactic acid bacteria is used in malolactic fermentation. Process Decarboxylation occurs. Dicarboxylic acid converted to monocarboxylic acid. Malic acid(dicarboxylic acid) + Leuconostoc sp. ------> lactic acid (monocarboxylic acid) Importance PH increases means acidity decreases, this step changes the wine flavour from acidic to little sweet & gives a creamy texture to wine. Hope this post will help you (~Bio blog) Other posts http://bioblogsworld.blogspot.com/2022/07/enzyme-immobilization.html http://bioblogsworld.blogspot.com/2022/07/negative-staining-method.html https://bioblogsworld.blogspot.com/2022/12/corynebacterium-diphtheriae.html
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Enzyme immobilization

Enzyme immobilization is a method in which an enzyme of interest is entrapped in a gel matrix. That can be use in other experiments. Alginate(alginic acid) along with sodium salt which is sodium alginate is soluble in water, but when this alginate is present with a divalent cation, like Ca2++, it becomes water insoluble. Materials 1. Sodium alginate solution. 2. Enzyme of our interest. 3. calcium chloride solution. 4. Syringe. Procedure 1. Specific amount of enzyme is mixed in sodium alginate solution. 2. Using a syringe this mixture is drop wise poured in calcium chloride solution. 3. Beads formation occurs. Result White or transparent gel beads form. When the mixture is poured in calcium chloride solution, the sodium ion of the alginate is substituted by the calcium ion and sodium alginate is converted to calcium alginate, which is insoluble to water that's why forms bead. The enzyme is entrapped inside the gel beads. Hope this post will help you          ...
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Negative staining method

Negative staining is a type of staining procedure where we can observe live cells. Now dyes are toxic to cells, but here in case of negative staining stains are not taken up by cells, because here the stain use has same charge as the outer layer of cells that repels the stain. We see clear cells in dark background. Materials Glass slides Inoculating loop Nigrosin or indian ink Distilled water Spirit lamp Procedure 1. Take a greese free slide. 2. Take a drop of water in one side of the slide. 3. Take sample using inoculating loop and mix with the water. 4. Now, take a drop of the ink and mix with the water drop. 5. Take another slide, and touch the edge of the second slide with the drop mix, hold the other slide in 60 degree angle. 6. Now, make a smear by sliding the second slide upon the first slide 7.air dry the slide. 8. Observe under microscope. Observation and result White clear cells will be observed against a black background . Hope this post will help you       ...
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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...
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