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MICROBIAL BIOTECHNOLOGY: SCOPE, TECHNIQUES CONTD..

ZARAGOZIC ACIDS (SQUALESTATINS):
Over 93% of the cholesterol in the human body is located in cells, where it
performs indispensable structural and metabolic roles. The remaining 7%

circulates in the plasma,where it contributes to atherosclerosis (formation of plaques on the walls of the arteries supplying the heart, the brain, and other vital organs). For delivery to tissues, plasma cholesterol is packaged in lipoprotein particles;two thirds is associated with low-density lipoprotein(LDL) and the balance with the  high-density lipoprotein.
The disorder familial hypercholesterolemia occurs in one in 500 of the
population and results in elevated plasma levels of cholesterol-bearing LDL.
Male heterozygotes with dominant familial hypercholesterolemia have an
85% chance of occurrence of heart attacks (myocardial infarction) before
the age of 60. (Homozygotes of either sex die of heart disease at an early
age). A much larger number of people, who do not have familial hypercholesterolemia, have plasm…

Microbial Biotechnology: Scope, Techniques, Examples Continued..

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SECONDARY METABOLITES AS A SOURCE OF DRUGS:
Microorganisms produce a huge number of small molecular weight compounds that are broadly described as secondary metabolites. A traditional
approach to the discovery of new, naturally occurring bio active molecules
utilizes “screens.” A screen is an assay procedure that allows testing of numerous compounds for a particular activity. Tens of thousands of secondary
metabolites and other compounds have been examined for biological activity in various organisms and many have proved invaluable as antibacterial or 
anti fungal agents,anticancer drugs,immunosuppressants,herbicides,tools

for research, and the like. Genetically modified microorganisms have been engineered to produce
such compounds in large amounts. Among these, antibiotics are the secondary metabolites considered among the most important to human therapeutics, and the most extensive use of screens is in the search for compounds with selective toxicity for bacteria, fungi, or protozoa. It is…

Microbial Biotechnology: Scope, Techniques, Examples.

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One can be a good biologist without necessarily knowing much about microorganisms, but one cannot be a good microbiologist without a fair basic knowledge
of biology! – Stanier, R. Y., Doudoroff, M., and Adelberg, E. A. (1957).The
Microbial World. p. vii, Englewood Cliffs, NJ: Prentice-Hall, Inc.

Microorganisms, whether cultured or represented only in environmental
DNA samples, constitute the natural resource base of microbial biotechnology. Numerous prokaryotic and fungal genomes have been completely
sequenced and the functions of many genes established. For a newly
sequenced prokaryotic genome, functions for over 60% of the open reading frames can be provisionally assigned by sequence homology with genes
of known function. Knowledge of the ecology, genetics, physiology, and
metabolism of thousands of prokaryotes and fungi provides an indispensable complement to the sequence database.
This is an era of explosive growth of analysis and manipulation of microbial genomes as well as of invention o…

METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL MICROBIOLOGY PRODUCTS CONTD..

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PATHWAYS FOR THE SYNTHESIS OF PRIMARY AND SECONDARY METABOLITES OF
INDUSTRIAL IMPORTANCE:

The main source of carbon and energy in industrial media is carbohydrates. In recent times hydrocarbons have been used. The catabolism of these compounds will be discussed briefly because they supply the carbon skeletons for the synthesis of primary as well as for secondary metabolites.
The inter-relationship between the pathways of primary and the secondary metabolism will also be discussed briefly.
Catabolism of Carbohydrates:
Four pathways for the catabolism of carbohydrates up to pyruvic acid are known. All
four pathways exist in bacteria, actinomycetes and fungi, including yeasts. The four pathways are the Embden-Meyerhof-Parnas, the Pentose Phosphate Pathways, the Entner Doudoroff pathway and the Phosphoketolase. Although these pathways are for the breakdown of glucose. Other carbohydrates easily fit into the cycles.
(i) The Embden-Meyerhof-Parnas (EMP Pathways): The net effect of this pathway is

METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL MICROBIOLOGY PRODUCTS CONTD..

TROPHOPHASE-IDIOPHASE RELATIONSHIPS IN THE PRODUCTION OF SECONDARY PRODUCTS: 

From studies on Penicillium urticae the terms trophophase and idiophase were introduced
to distinguish the two phases in the growth of organisms producing secondary
metabolites. The trophophase (Greek, tropho = nutrient) is the feeding phase during
which primary metabolism occurs. In a batch culture this would be in the logarithmic
phase of the growth curve. Following the trophophase is the idio-phase (Greek, idio = peculiar) during which secondary metabolites peculiar to, or characteristic of, a given organism are synthesized.
 Secondary synthesis occurs in the late logarithmic, and in the
stationary, phase. It has been suggested that secondary metabolites be described as 'idiolites' to distinguish them from primary metabolites.

ROLE OF SECONDARY METABOLITES IN THE PHYSIOLOGY OF ORGANISMS PRODUCING THEM:
Since many industrial microbiological products result from secondary metabolism,
workers have sought to ex…

MICROBIOLOGY : METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL ...

MICROBIOLOGY : METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL ...: THE NATURE OF METABOLIC PATHWAYS: In order to be able to manipulate microorganisms to produce maximally materials of economic importance...

MICROBIOLOGY : METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL ...

MICROBIOLOGY : METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL ...: THE NATURE OF METABOLIC PATHWAYS: In order to be able to manipulate microorganisms to produce maximally materials of economic importance...

METABOLIC PATHWAYS FOR BIOSYNTHESIS OF INDUSTRIAL MICROBIOLOGY PRODUCTS

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THE NATURE OF METABOLIC PATHWAYS:

In order to be able to manipulate microorganisms to produce maximally materials of
economic importance to humans, but at minimal costs, it is important that the physiology
of the organisms be understood as much as is possible. In this section  relevant elements
of the physiology of industrial organisms will be discussed.
A yeast cell will divide and produce carbon dioxide under aerobic conditions if offered a solution
of glucose and ammonium salts. The increase in cell number resulting from the growth
and the bubbling of carbon dioxide are only external evidence of a vast number of chemical reactions going in the cell. The yeast cell on absorbing the glucose has to produce various
proteins which will form enzymes necessary to catalyze the various reactions concerned
with the manufacture of proteins, carbohydrates, lipids, and other components of the cell
as well as vitamins which will form coenzymes. A vast array of enzymes are produced as
the glucose and ammoni…

ASPECTS OF MOLECULAR BIOLOGY & BIOINFORMATICS RELEVANCE IN INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY CONTD..

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METAGENOMICS:
Metagenomics is the genomic analysis of the collective genome of an assemblage of
organisms or ‘metagenome.’Metagenomics describes the functional and sequence-based
analysis of the collective microbial genomes contained in an environmental sample.
 Other terms have been used to describe the same method, including
environmental DNA libraries, zoolibraries, soil DNA libraries, eDNA libraries,
recombinant environmental libraries, whole genome treasures, community genome,
whole genome shotgun sequencing. The definition applied here excludes studies that
use PCR to amplify gene cassettes or random PCR primers to access genes of interest since these methods do not provide genomic information beyond the genes that are amplified.
Many environments have been focus of metagenomics, including the soil, the oral cavity,feces, and aquatic habitats, as well as the hospital metagenome a term intended to encompass the genetic potential of organisms in hospitals that contribute to public health c…