microbiology

Utilization of energy & Bio-synthesis:

Utilization of energy & Bio-synthesis Vasanthan_V 09MTBI29

ATP syhthesis:

Energy is stored in the form of high-energy-transfer compounds(of which ATP is most imp..). The principle of coupling exergonic reactions to endergonic reactions requires the utilization of high-energy-transfer compounds like ATP. An electrochemical proton gradient may result in ATP synthesis,but it can also be used for other biological purposes like generating heat and rotation of bacterial flagella. ATP syhthesis

Biosynthetic processes:

In cell biosynthetic processes requires energy. Energy from ATP is used to convert one chemical substance into another and to synthesize complex substances from simpler ones. Biosynthetic processes

Biosynthetic processes involves:

Synthesis of small molecules: THE AMINO ACIDS Synthesis of macro molecules: THE STRUCTURE AND BIOSYNTHESIS OF A CELL WALL PEPTIDOGLYCAN THE BIOSYNTHSIS OF DNA(DeoxyriboNucleicAcid) PROCESS OF PROTEIN SYNTHESIS Biosynthetic processes involves

Synthesis of small molecules: THE AMINO ACIDS:

Amino acids,of which there are about 20,are the building blocks of proteins. The sequence & manner in which in which they are linked determine the type of protein they form. A microorganism growing in a medium may have all 20 of amino acids present in the medium;that is ,they are available for the microbe,performmed in the medium. If they are not available freely in the medium,the microorganism may have to liberate amino acids from proteins by the action of intracellular or extracellular proteolytic enzymes. Synthesis of small molecules: THE AMINO ACIDS

Slide 8:

Biosynthesis of threonie In utilization of atp interconversion

Biosynthesis of In utilization of atp interconversion:

Biosynthesis of In utilization of atp interconversion

Synthesis of macromolecules: the structure and biosynthesis if a cell-wall peptidoglycan:

In cell,major end prodts of biosynthesis are proteins and nucleic acids. However, they are macromolecular peculiar to the prokaryotes which require specialized biosynthetic processess. This also serves as a example of how polymers are synthesized outside the membrane. Synthesis of macromolecules: the structure and biosynthesis if a cell-wall peptidoglycan

Structure of peptidoglycan:

Rigid wall of cell wall structure is Murein Peptidoglycan Mucopeptide . Walls of gram + ve bacteria contains large amount of peptidoglycan . Gram – ve has smaller proportion. Peptidoglycan has three buliding blocks Acetylglycosamine (AGA or GlcNAc ) Acrtylmuramic acid(AMA or MurNAc ) A peptide containing of 4 or 5 amino acids of limited varity . Structure of peptidoglycan

Activation of peptidoglycan precursor :

E.coli can synthesize cell-wall peptidoglycan when grown in a simple medium of glucose, Ammonium sulfate,and mineral salts. Activation of peptidoglycan precursor

Peptidoglycan synthesis Sometimes loosely referred to as cell wall synthesis ….:

Precursors synthesised in the bacterial cell • Lipid carrier – bactoprenol essential role – Very hydrophobic C55 alcohol – Bonds to N-acetyl glucosamine/N-acetyl muramic acid/pentapeptide peptidoglycan precursors – Transports precursors across the cytoplasmic membrane by rendering them hydrophobic enough to pass through – Once in periplasm bactoprenol interacts with that insert cell wall precursors into the growing point of the cell wall and catalyse glycosidic bond formation Peptidoglycan synthesis Sometimes loosely referred to as cell wall synthesis ….

Transpeptidation :

• Final step in peptidoglycan synthesis • Involves formation of peptide cross-links between muramic acid residues in adjacent chains • 'penicillin-binding proteins' in the outer leaf of the cell membrane responsible for this step – enzymes responsible for the final stages of assembly of the peptidoglycan molecule – up to 4 in Gram positive bacteria, up to 11 in Gram negative bacteria – PBPs use a serine containing molecule to bond covalently with the peptidoglycan chains Transpeptidation

The biosynthesis of dna (Deoxyribonucleic acid):

Another DNA is a template; in the biosynthesis of protein molecule of RNA is the template. STUCTURE OF DNA DNA from any cell is a long rope like molecule compossed of 2 strands,wound to form double helix. Proposed by james watson & francis crick. The biosynthesis of dna (Deoxyribonucleic acid)

Breakdown of DNA into lower mocular weight cmpds.,:

DNA NUCLEOTIDES NUCLEOSIDES PHOSPHORIC ACID PURINE BASE PYRIMIDINE BASE SUGAR (ADENINE, (CYTOSINE, (2-DEOXY GUANINE) THYMINE) RIBOSE) Breakdown of DNA into lower mocular weight cmpds .,