MICROBIAL METABOLISM

3. BIOTECHNOLGY

5. MICROBIAL
METABOLISM
All biochemical reactions in microbes
to generate energy.

6. GLYCOLYSIS:-

7. GLYCOSIS:-
• The sequential breakdown
of glucose into pyruvic acid.
• C6H12O6 + 2NAD + 2ADP
+2Pi → 2 CH3COCOOH
+2NADH2 + 2ATP
• Two NADP and two ATP are
the net gain of energy.

8.  SITE OF GLYCOLYSIS:-
Cytosol of cytoplasm
TYPES OF GLYCOLYSIS:-
 Aerobic glycolysis
Glucose fermentation→ Intermediate
(pyruvate) respiration (O2) → CO2 +H2O
 Anaerobic glycolysis
Glucose fermentation→ fermentation product
(lactic acid /Ethyl alcohol)

9. STEPS OF GLYCOLYSIS:-
 11 enzymes with 11 steps.
 Partitioned into two main steps.

10. ❖ Step # 1: Synthesis of glucose 6 phosphate:-

11. ❖ Step # 2 : Isomerization to Fructose-6-
phosphate:-

12. ❖ Step # 3+4 :formation of fructose 1,6-
bisphosphate:-

13. Step # 5: Interconversion of triose
phosphate:-

14. ❖ Step #6 : Phosphorylation of G3P To BGP:-

15. ❖ Step # 7: Formation of 3-phosphoglycerate:-

16. ❖ Step # 8: Conversion of 3-phosphoglycerate:-

17. ❖ Step # 9 : Formation of phospho-enol
pyruvate:-

18. ❖ Step # 10: Pyruvate formation:-

19. GLYCOLYSIS CYCLE :-
Main steps
PREPARATORY PHASE:-
Glucose activation phase with 1,2,3,4,5 steps
of glycolysis where ATP is utilized.
PAYOFF PHASE:-
Energy extraction phase with the formation
of coupled ATP including last four steps of glycolysis.

20. PREPARATORY PHASE:-

21. PAY OFF PHASE:-

22. GLYOXALATECYCLE:-

23. GLYOXALATE
CYCLE:-
Variation of
the tricarboxylic acid
cycle in plants,
bacteria, protists and
fungi.

24. REACTION IN GLY-OXYSOMES:-
I. Acetyl-CoA:-

25. STEPS OF
GLYOXALATE CYCLE:-
 REACTION IN
GLYOXYSOMES.
 REACTION
IN ITROCHONDRIA.
 REACTION IN CYTOSOL.

26. II. Citric Acid:-

27. III. Cis-aconitic:-

28. IV. Iso-citric acid

29. V. Glyoxylic acid:-

30. VI. Malic acid:-

31. REACTION IN MITROCHONDRIA:-
VII. Succinic acid:-

32. VIII. Oxalo-acetic:-

33. REACTION IN CYTOSOL
IX. PHOSPHOENOL PYRUVIC ACID:-
 It moves into cytosol.
 By reverse glycolysis, fructose and glucose
phosphates are formed.
X. Sucrose:-
 Finally, sucrose is formed.

34. DIFFERENCE BETWEEN TCA AND GLOXALATE
CYLE:-
TCA CYCLE
•Isocitrate is converted
into glyoxylate and
succinate by alpha
ketoglutarate.
•It uses eight enzymes
GYLOXALTAE CYLCLE
•Isocitrate is converted
into glyoxylate and
succinate by ICL.
•It uses five enzymes.

35. Significance of glyoxylate pathway :
i. It is gluconeogenesis reaction.
ii. Bypass of TCA cycle.
iii. In nematodes, on early stage of emryogenesis.
iv. In bacteria, cultured in acetate rich carbon source

36. TRICARBOXYLIC ACID CYCLE (TCA)

37. TRICARBOXYLIC
ACID CYCLE (TCA):-
A series of enzyme
catalyzed reaction used
by all aerobic organism to
release stored energy
through the oxidation of
acetyl Co-A.

38. Microbial TCA
cycle:-
In prokaryotes, TCA cycle
takes place in cytosol I.e;
biomembrane rather
than inner mambrane as
it lackls mitrochondria.

39. DISCOVERY:-
INITIATION
• Discovered in 1930 by
Albert Szent Gyorgyi.
FINAL IDENTIFICATION:-
• finally identified in 1937 by
Hans Adolf Krebs and William
Arthur Johnson.
EVOLUTION:-
 Evolved from anaerobic bacteria.
 Initiator is acetyl-CoA.

40. STEPS OF CITRIC ACID OR TCA CYCLE:-
• Irreversible, extends the 4C oxaloacetate to a 6C molecule.
• Reversible isomerization.
• Generates NADH (equivalent of 2.5 ATP).
• Rate-limiting, irreversible stage, generates a 5C molecul.e
• Irreversible stage, generates NADH.
• Condensation reaction of GDP+ Pi and hydrolysis of Succinyl-CoA.
• Uses FAD as a prosthetic group (FAD→FADH2 in the first step of the
reaction).
• Hydration of C-C double bond.
• Reversible (in fact, equilibrium favors malate), generates NADH.

41. • Citrate
synthase
• Aldol
condensation
Oxaloacetate + Acetyl
CoA + H2O
• Aconitase
• Dehydration
Citrate + CoA-SH

42. • Aconitase
• Hydration
cis-Aconitate +
H2O
• Isocitrate
dehydrogenase
• Oxidation
Isocitrate+ NAD+

43. • Isocitrate
dehydrogenase
• Decarboxylation
Oxalo-
succinate+ NADH
+ H +
• α-Ketoglutarate
dehydrogenase
• Oxidative
decarboxylation
α-Ketoglutarate+
NAD+ + CoA-SH

44. • Succinyl-CoA
synthetase
• substrate-level
phosphorylation
Succinyl-CoA+ GDP + Pi
• Succinate
dehydrogenase
• Oxidation
Succinate + ubiquinone(
Q)

45. • Fumarase
• Hydration
Fumarate +H2O
• Malate
dehydrogenase
• Oxidation
L-
Malate + NAD+