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Antibiotics are used to treat or prevent some types of bacterial infection. They work by killing bacteria or preventing them from reproducing and spreading.
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Https://www.quora.com/What-is-industrial-microbiology
http://nsdl.niscair.res.in/jspui/bitstream/123456789/129/1/Metabolites.pdf
http://www.123seminarsonly.com/Seminar-Reports/028/59666030-21960402-Industrial-Microbiology.pdf
http://fac.ksu.edu.sa/sites/default/files/industerial_microbiology-2-3.pdf!!!
Primary Metabolites
Primary metabolites are involved in growth, development, and reproduction of the organism. The primary metabolite is typically a key component in maintaining normal physiological processes; thus, it is often referred to as a central metabolite. Primary metabolites are typically formed during the growth phase as a result of energy metabolism, and are deemed essential for proper growth. Examples of primary metabolites include alcohols such as ethanol, lactic acid, and certain amino acids. Within the field of industrial microbiology, alcohol is one of the most common primary metabolites used for large-scale production. Specifically, alcohol is used for processes involving fermentation which produce products like beer and wine. Additionally, primary metabolites such as amino acids-- including L-glutamate and L-lysine, which are commonly used as supplements-- are isolated via the mass production of a specific bacterial species, Corynebacteria glutamicum. Another example of a primary metabolite commonly used in industrial microbiology includes citric acid. Citric acid, produced by Aspergillus niger, is one of the most widely used ingredients in food production. It is commonly used in pharmaceutical and cosmetic industries as well.
Aspergillus niger
Microorganisms such as Aspergillus niger are used in industrial microbiology for mass production of citric acid.
Secondary Metabolites
Secondary metabolites are typically organic compounds produced through the modification of primary metabolite synthases. Secondary metabolites do not play a role in growth, development, and reproduction like primary metabolites do, and are typically formed during the end or near the stationary phase of growth. Many of the identified secondary metabolites have a role in ecological function, including defense mechanism(s), by serving as antibiotics and by producing pigments. Examples of secondary metabolites with importance in industrial microbiology include atropine and antibiotics such as erythromycin and bacitracin. Atropine, derived from various plants, is a secondary metabolite with important use in the clinic. Atropine is a competitive antagonist for acetycholine receptors, specifically those of the muscarinic type, which can be used in the treatment of bradycardia. Antibiotics such as erythromcyin and bacitracin are also considered to be secondary metabolites. Erythromycin, derived from Saccharopolyspora erythraea, is a commonly used antibiotic with a wide antimicrobial spectrum. It is mass produced and commonly administered orally. Lastly, another example of an antibiotic which is classified as a secondary metabolite is bacitracin. Bacitracin, derived from organisms classified under Bacillus subtilis, is an antibiotic commonly used a topical drug. Bacitracin is synthesized in nature as a nonribosomal peptide synthetase that can synthesize peptides; however, it is used in the clinic as an antibiotic.
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Source: Boundless. “Primary and Secondary Metabolites.” Boundless Microbiology Boundless, 26 May. 2016. Retrieved 20 Jan. 2017 from https://www.boundless.com/microbiology/textbooks/boundless-microbiology-textbook/industrial-microbiology-17/industrial-microbiology-198/primary-and-secondary-metabolites-999-5345/
Primary metabolites are involved in growth, development, and reproduction of the organism. Examples of primary metabolites include amino acids, enzymes, purin nucleotides, vitamins and organic acids.
Secondary metabolites are produced by the modification of primary metabolites. They do not play any role in growth, development, and reproduction like primary metabolites. They are formed during or near the stationary phase of growth. Examples of secondary metabolites with importance in industrial microbiology include antibiotics, toxins, alkaloids, plant growth factors.
Principles of overproduction of primary and secondary metabolites Fermentation is enzymatically controlled transformation of an organic compound. The fermentation product may be a metabolite or biomass. Metabolites are the intermediates and products of metabolism. The term metabolite is generally restricted to small molecules. The microorganisms during growth phase (trophophase) synthesize a range of metabolites that are essential for normal growth, development and reproduction and collectively called primary metabolites. Amino acids, organic acids, alcohol, nucleotides and enzymes are some of products of primary metabolism that have industrial significance. After growth phase the microbe enters in stationary phase (idiophase) due to exhaustion of nutrients in the medium. In this phase, active growth of the microorganism ceased and some microorganisms produce metabolite, which are not essential for growth and reproduction. These metabolites are referred as secondary metabolites. Secondary metabolism produces diverse, often species-specific end-products like alkaloids, antibiotics, toxins and some pigments that have commercial value.
The microbial metabolites are produced through fermentation and their overproduction is of prime importance to shorten the production time and space and at the same time reducing the product cost. Overproduction of metabolites depends on the genetic makeup of microbial strain and the environmental conditions under which the fermentation is carried out. To increase the production of fermentation product, different approaches applied are as follows.
Производство продуктов микробного синтеза первой фазы. К наиболее известным промышленным продуктам микробного синтеза относятся: ацетон, спирты (этанол, бутанол, изопропанол, глицерин), органические кислоты (лимонная, уксусная, молочная, глюконовая, итаконовая, пропионовая), ароматизаторы и вещества, усиливающие запахи (глутамат натрия). Спрос на последние постоянно увеличивается из-за тенденции к употреблению малокалорийной и растительной пищи, для придания вкусу и запаху пищи разнообразия. Ароматические вещества растительного происхождения можно производить путём экспрессии генов растений в клетках микроорганизмов. Методом генной инженерии в клетки Е. coli введён ген, кодирующий синтез а-антитрипсина человека, ингибирующсго активность эластазы. Его образование бактериями достигает 15% синтеза всех клеточных белков. Таким образом получают препарат эглин, применяемый для компенсации врождённого отсутствия а-антитрипсина, приводящего к тяжёлой форме эмфиземы лёгких. Иммуномодулятор бестатин, ингибитор поверхностных пептидаз лимфоцитов, продуцирует Streptococcus olivoretuculi. Микроорганизмы — продуценты ингибиторов других важных в медицине ферментов. Например, ингибитор амилазы, синтезируемый Streptococcus tendae, блокирует гидролиз крахмала и снижает содержание сахара в крови; назначается больным диабетом. Каптоприл из культуральной жидкости стрептококков препятствует образованию ангиотензина II и снижает артериальное давление (АД) у гипертоников.
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Производство продуктов микробного синтеза второй фазы. С использованием микроорганизмов получают витамины В1, В2 (продуценты— бактерии, грибы родов Candida, Pichia, Ashbya); фолиевую, пантотеновую кислоты, пиридоксаль, витамин В12 (продуценты — Propionibacterium shermanii, Pseudomonas denitrificam или метаногенные бактерии). Витамин С производят путём химического синтеза, однако этап высокоселективного дегидрирования D-сорбита в L-сорбозу осуществляют с помощью уксуснокислых бактерий.
Inductrial Microbilogy
- industrial products from microorganisms
Antibiotics
Infections have been the major cause of diseases throughtout the history. microbiosynthesis
Doses of antibiotics can be provided in several ways:
- oral antibiotics – tablets, capsules or a liquid that you drink, which can be used to treat most types of mild to moderate infections in the body
- topical antibiotics – creams, lotions, sprays or drops, which are often used to treat skin infections
- injections of antibiotics – these can be given as an injection or infusion through a drip directly into the blood or muscle, and are usually reserved for more serious infections
Antibiotics are used to treat or prevent some types of bacterial infection. They work by killing bacteria or preventing them from reproducing and spreading.
Antibiotic resistance can either be inherent or acquired. Some bacteria are naturally resistant to some antibiotics due to their physiological characteristics. This is inherent resistance. Acquired resistance occurs when a bacterium that was originally sensitive to an antibiotic develops resistance. For example resistance genes can be transferred from one plasmid to another plasmid or chromosome, or resistance can occur due to a random spontaneous chromosomal mutation.
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Types of antibiotics
There are hundreds of different types of antibiotics, but most of them can be broadly classified into six groups. These are outlined below.
- penicillins (such as penicillin and amoxicillin) – widely used to treat a variety of infections, including skin infections, chest infections and urinary tract infections
- cephalosporins (such as cephalexin) – used to treat a wide range of infections, but some are also effective for treating more serious infections, such as septicaemia and meningitis
- aminoglycosides (such as gentamicin and tobramycin) – tend to only be used in hospital to treat very serious illnesses such as septicaemia, as they can cause serious side effects, including hearing loss and kidney damage; they're usually given by injection, but may be given as drops for some ear or eye infections
- tetracyclines (such as tetracycline and doxycycline)– can be used to treat a wide range of infections, but are commonly used to treat moderate to severe acne and rosacea
- macrolides (such as erythromycin and clarithromycin) – can be particularly useful for treating lung and chest infections, or an alternative for people with a penicillin allergy, or to treat penicillin-resistant strains of bacteria
- fluoroquinolones (such as ciprofloxacin and levofloxacin) – broad-spectrum antibiotics that can be used to treat a wide range of infections
The biggest worry is that new strains of bacteria may emerge that can't be effectively treated by any existing antibiotics.
Fermentative activity of microbes is used industrially to obtain a number of products. The two common ones are alcoholic fermentation and antibiotics.
Methodology:
For any new industrial utilisation of a microbial activity, the technology passes through three stages—laboratory scale, pilot plant scale and manufacturing unit. The development from laboratory scale to manufacturing unit is called scaling up.
1. Laboratory Scale:
Soon after the discovery of use of a microorganism, the maximum number of strains is searched and the most suitable strain is selected and multiplied. A laboratory scale apparatus/plant is manufactured. It has a glass fermentor (fermenter). All the parameters of the process are worked out like nutrients for the microbe, pH, aeration, disposal of C02 if evolved, optimum temperature, by products, product inhibition or stimulation, time of optimum production, separation of product and its purification. Ultimately, the laboratory scale process is finalised.
2. Pilot Plant Scale:
It is intermediate stage where working of the laboratory scale process is tested cost and qualities of the product are evaluated. Glass vessels are replaced by metallic containers. The container where fermentation is carried out is called bioreactor or fermentor. Aeration system, pH corrections and temperature adjustments are perfected.
3. Manufacturing Unit:
Its size is determined by the economics worked at during the pilot plant scale process. Bioreactor or fermentor is often large. Microorganisms are added in bioreactors in three ways:
(i) Support growth system or on surface of nutrient medium,
(ii) Suspended growth system or suspended in nutrient medium,
(iii) Column or immobilised growth system where microorganisms placed in calcium alginate beads are kept in columns.
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Broad Spectrum Antibiotic. It is an antibiotic which can kill or destroy a number of pathogens that belong to different groups with different structure and wall composition. Specific Antibiotic. It is an antibiotic which is effective only against one type of pathogens.
Antibiotics function either as bactericides (killing bacteria) or bacteriostatic (inhibiting growth of bacteria). This is done by (i) Disruption of wall synthesis, e.g., penicillin, cephalosporins, bacitracin, (ii) Disruption of plasmalemma repair and synthesis, e.g., polymyxin, nystatin, amphotericin, (iii) Inhibition of 50 S ribosome function, e.g., erythromycin. (iv) inhibition of 30 S ribosome function, e.g., streptomycin, neomycin, (v) Inhibition of aa-tRNA binding to ribosome, e.g., tetracycline, (vi) Inhibition of translation, e.g., chloramphenicol.
Characteristics of a Good Antibiotic:
(a) Harmless to host with no side effect,
(b) Harmless to normal microflora of alimentary canal,
(c) Ability to destroy pathogen as well as broad spectrum,
(d) Effective against all strains of pathogen,
(e) Quick action.
Resistance to antibiotics comes from (i) Development of copious mucilage, (ii) Alteration of cell membrane so that antibiotic cannot recognise the pathogen, (iii) Alteration of cell membrane which prevents antibiotic entry, (iv) Change to L-form by pathogen, (y) Mutation in pathogen. (vi) Development of pathogen enzyme capable of modifying antibiotic.
Uses:
Antibiotics are used:
(i) As medicines for treatment of a number of pathogenic or infectious diseases. Because of antibiotics and their newer more potent forms, a number of formidable diseases are now curable, e.g., plague, typhoid, tuberculosis, whooping cough, diphtheria, leprosy, etc.
(ii) As preservatives in perishable fresh food articles (e.g., meat and fish), pasteurised and canned foods,
(iii) As feed supplement for animals, especially poultry birds because they enhance growth.
Chemicals, Enzymes and Other Bioactive Molecules:
Microbes are being used for commercial and industrial production of certain chemicals like organic acids, alcohols, enzymes and other bioactive molecules. Bioactive molecules are those molecules which are functional in living systems or can interact with their components. A number of them are obtained from microbes.
Organic Acids:
A number of organic acids are being manufactured with the help of microbes. The important ones are as follows:
1. Acetic Acid:
It is prepared from fermented alcohols with the help of acetic acid bacteria, Acetobacter aceti. Alcoholic fermentation is anaerobic process, but the conversion of alcohol to acetic acid is aerobic one.
As soon as 10-13% acetic acid is formed, the liquid is filtered. It is used after ripening as vinegar. The type and quality of vinegar depends upon substrate used for alcoholic fermentation and ripening. For other purposes, acetic acid is purified. The organic acid is employed in pharmaceuticals, colouring agents, insecticides, plastics, etc.
2. Citric Acid:
It is obtained through the fermentation carried out by Aspergillus niger and Mucor species on sugary syrups. Yeast Candida lipolytica can also be employed, provided its nutrient medium is made deficient of iron and manganese. Citric acid is employed in dyeing, engraving, medicines, inks, flavouring and preservation of food and candies.
3. Lactic Acid:
It was the first organic acid to be produced from the microbial fermentation in starchy and sugary medium. Lactic acid fermentation is carried out by both bacteria (e.g., Streptococcus lactis, Lactobacillus species) and fungi (e.g., Rhizopus). The acid derived from fungal sources is costlier but is of high purity. Any starchy or sugary medium is used.
Lactic acid is used in confectionery, fruit juices, essences, pickles, curing of meat, lemonades, canned vegetables and fish products. It is also employed as mordant in tanning, printing of wool in the preparation of plastics and pharmaceuticals.
4. Gluconic Acid:
The acid is prepared by the activity of Aspergillus niger and Penicillium species. Calcium gluconate is used widely as a source of calcium for infant, cows and lactating mothers. It is also used in preparation of pharmaceuticals.
5. Butyric Acid:
The acid is produced during fermentation activity of bacterium Clostridium acetobutylicum. Rincidity of butter is also due to its formation.
6. Alcohols:
Ethanol, methanol, propanol and butanol are alcohols that can be produced commercially by fermentation activity of some fungi (e.g., Yeast, Mucor, Rhizopus) and bacteria (e.g., Clostridium acetobutylicum, C. saccharotobutylicum). The alcohols are important industrial solvents.
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Enzymes:
Enzymes are proteinaceous substances of biological origin which are capable of catalysing biochemical reactions without themselves undergoing any change. The word enzyme was coined by William Kuhne (1867) after the fact the yeast provided the most well studied bio-catalytically controlled reactions of alcoholic fermentation (Gk. en- in, zyme- yeast). Buchner (1901) found yeast extract to have enzymatic activity. The number of enzymes now runs into several thousands.
All of them are macromolecules (large sized molecules) with a specific three-dimensional shape. Enzymes are substrate specific and carry out a specific catalytic action. They work best at room temperature and near-neutral pH with the exception of several digestive enzymes. Use of enzymes in biotechnology had a number of problems which have been largely overcome by the technique of immobilisation of enzymes inside artificial cells or gels. About 300 enzymes are being used in industry and medicines. Most of them are obtained from microbes.
1. Proteases:
They are enzymes that degrade proteins and polypeptides. Proteases are obtained from Mortierella renispora, Aspergillus and Bacillus species. The enzymes are used in:
(i) Clearing (Chill proofing) beer and whisky,
(ii) Cleaning of hides,
(iii) Softening of bread and meat,
(iv) Degumming of silk,
(v) Manufacture of liquid glue,
(iv) Manufacture of detergents capable of removing proteinaceous stains.
2. Amylases:
They degrade starches. Amylases are obtained from Aspergillus, Rhizopus and Bacillus species. The enzymes are employed for:
(i) Softening and sweetening of bread,
(ii) Production of alcoholic beverages (e.g., beer, whisky) from starchy materials,
(iii) Clearing of turbidity in juices caused by starch,
(iv) Separation and desizing of textile fibres.
Amylase, glucoamylases and glucoisomerases are employed in conversion of com starch into fructose rich com syrup. Incidentally fructose is the sweetest of the sugars. Therefore, com syrup is sweeter than sucrose solution. It is used in sweetening and flavouring soft drinks, biscuits, cakes, etc.
3. Rennet:
It is an extract from the stomach of calf that contains enzyme rennin. Rennet or chymosin is now being obtained from Mucor and Endothio species. Withania and fig (ficin) also yield similar product.
4. Lactases:
They are obtained from Saccharomyces fragilis and Torula cremoris. The enzymes convert lactose (milk sugar) into lactic acid. Lactic, acid can coagulate milk protein, casein. Lactases prevent crystals formation (sandiness) in dairy preparations like ice-cream and processed cheese.
5. Streptokinase (Tissue Plasminogen Activator or TPA):
It is an enzyme obtained from the cultures of some haemolytic bacterium Streptococcus and modified genetically to function as clot buster. It has fibrinolytic effect. Therefore, it helps in clearing blood clots inside the blood vessels through dissolution of intravascular fibrin.
6. Pectinases:
They are obtained commercially from Byssochlamys fulvo. Along-with proteases, they are used in clearing of fruit juices. Other uses are in retting of fibres and preparation of green coffee.
7. Lipases:
They are lipid dissolving enzymes that are obtained from Candida lipolytica and Geotrichum candidum. Lipases are added in detergents for removing oily stains from laundry. They are also used in flavouring cheese.
Cyclosporin A:
It is an eleven membered cyclic oligopeptide obtained through fermentative activity of fungus Trichoderma polysporum. It has antifungal, anti-inflammatory and immunosuppressive properties. It inhibits activation of T-cells and therefore, prevents rejection reactions in organ transplantation.
Statins:
They are products of fermentation activity of yeast Monasciis purpureus which resemble mevalovate and are competitive inhibitors of p-hydroxy-p-methylglutaryl or HMG CoA reductase. This inhibits cholesterol synthesis. Statins are, therefore, used in lowering blood cholesterol, e.g., lovastatin, pravastatin, simvastatin.
Производство вакцин
Традиционные методы производства вакцин основаны на применении ослабленных или убитых возбудителей. В настоящее время многие новые вакцины (например, для профилактики гриппа, гепатита В) получают методами генной инженерии.
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