GENES The gene is a nucleic acid sequence that is necessary for function of gene product. Gene may be a protein coding gene whose transcribed RNA is translated into proteins or RNA only genes. Protein coding genes may be solitary or families or tandem repeats NON –CODING SEQUENCE The non coding sequence are genes that do not encode the protein. The amount of non-coding sequence in DNA of organism varies among species. Eg-Human genome -98% non-coding genes Prokaryotes -10% non-coding genes Types of Non coding sequences The non coding sequences can be in the form of following Introns Anti leader and Anti trailer sequence Promoter sequence Enhancers Pseudogenes Gene fragments Telomeres Non-coding functional RNA Cis-Trans regulatory elements INTRONS Introns are non-coding sequence that transcribed into RNA But precursor mRNA removed by splicing during processing. The eukaryotic genome has large amount of introns...
1.Rxn with glycosidic OH
Rxn with methyl alcohol forms methyl gluconate
2.Rxn with alcoholic OH
Rxn with methyl iodide and water produce 2,3,4,6 methyl glucoside.It is also known as etherification.
3.Rxn with glycosidic and alcoholic OH group
Rxn with acetic anhydride produce glucose penta acetate .It is also called as esterification.
Reaction involving in aldehyde or ketone group
1.Reduction :
Glucose with sodium amalgam reduced to sorbitol .
Fructose with sodium amalgam reduced to sorbitol and mannitol mixture.
2.With mineral acid
Glucose with mineral acid form levulinic acid .
3.With dilute acids
Glucose with dilute acids known as lobry de Bruyn albreda Von ekestein reaction.It is also called endiol formation.
Glucose with weak acid form fructose or mannose
6.Reaction with HCN
Glucose with HCN is also known as killiani synthesis. In this reaction glycerose converted to erythrose and threose.
7.With alanine
Glucose with alanine form schiffs base.It is also known as browning reaction in Bread.It is also called milliard reaction .
8.With phenylhydrazine:
Glucose with phenylhydrazine form yellow crystalline insoluble compounds which is used for identification of sugars.It lead to glucose hydrazone to aldohydrazone and final product as osazone.
9.Reaction with hydroxyl amine
Glucose with hydroxylamine form oxime
10.Fermentation:
Glucose with yeast ferment to alcohol and carbon dioxide formation.
11.Reaction with metal hydroxide
Glucose with benidict solution gives green to yellow and to brown .Glucose to fehlings solution form brick red colour.
Glucose with barfoed reagent provide ref precipitate which is answered by monosacharides.With molisch reagent form brown ring which is answered by all carbohydrates.
Reaction with aldehyde/keto group or alcoholic OH group
1.With mild oxidants:
Reaction with mild oxidants form glucuronic acid by glucose whereas with strong oxidants form saccharic acid.
fructose with strong oxidants form mixture of trihydroxy glutaric acid,tartaric acid and glycollic acid.
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