Objects of industrial biotechnology

Principles of biotechnology and selection of objects

Industrial biotechnology relies on the close integration of advanced scientific developments and actual production facilities. It is based on processes such as fermentation, bioconversion (transformation of one substance into another), cultivation of biological objects, and genetic manipulations.

Despite enormous natural biodiversity (over 100 thousand species of bacteria and 250 thousand fungi), actual biotechnological production involves about 100 species. This strict limitation is dictated by the poor understanding of the vast majority of representatives of the microbial world. Successful work with a strain requires specialized equipment, strict control at all stages, and a deep understanding of the producer's physiology.

Bacteria and fungi as biological factories

In industry, different genera of microorganisms solve highly specialized tasks:

• Genus Acetobacter: oxidizes ethanol to produce acetic acid (with the release of carbon dioxide and water).
• Genus Bacillus: serves as a source of enzymes (e.g., B. subtilis) and the basis for plant protection products (B. thuringiensis).
• Genus Clostridium: used for the fermentation of sugars to form solvents — butanol, acetone, and ethanol.
• Lactic acid bacteria (Lactobacillus): indispensable in the food industry.
• Pseudomonads (P. denitrificans): used for the synthesis of vitamin B12.
• Corynebacteria (C. glutamicum): produce amino acids.

Among fungi, molds (Penicillium chrysogenum, Cephalosporium acremonium) and actinomycetes (Streptomyces spp.) play a crucial role as the main antibiotic producers. Yeast is actively used in baking, brewing, and winemaking, for the synthesis of feed protein, and also serves as an important component of laboratory nutrient media.

Medical and genetic engineering applications

A breakthrough in pharmacology is associated with the use of recombinant strains, into which foreign genetic material has been introduced by genetic engineering methods.

• Escherichia coli (E. coli) has become a universal producer: it produces interferons, insulin, growth hormones, and various antigens.
• Bacillus subtilis (B. subtilis) also efficiently produces interferon.
• Yeast cultures are used for the industrial synthesis of interleukins and hepatitis B virus antigens.
• Recombinant viruses (e.g., vaccinia virus) serve as a platform for producing viral antigens.

In addition to modified strains, native pathogenic, opportunistic, or vaccine strains are also used. They are necessary for the production of diagnostic agents, immunoglobulins, probiotics, and phage preparations.

Plant and animal cell cultures

When microorganisms cannot synthesize complex molecules, isolated cell cultures are used.

Plant cells have become a scalable alternative to harvesting wild-growing raw materials (for example, ginseng cell cultivation technology has been perfected). They synthesize opiates, alkaloids, vitamins, enzymes, and preparations of various groups (diuretics, cardiac, antitumor). The obtained substances are completely biologically equivalent to components from whole plants.

Animal cells are used to obtain cell products and as a substrate for virus replication when creating vaccines. Primary and continuous lines derived from tumor tissues or normal tissues (bone marrow, kidneys, lungs, skin, connective tissue) are used. To preserve the properties of the strain and prevent genetic mutations, the number of passages (subcultures) is kept to a minimum, and cultures are stored in liquid nitrogen.

Standard production stages

The technological chain of biotechnological synthesis is strictly standardized and includes five basic steps:

1. Selection of the producer: selection of the most productive and genetically stable strain.
2. Preparation of the medium: search for an optimal and economically viable nutrient base.
3. Cultivation: large-scale biomass accumulation using industrial equipment.
4. Isolation: purification of the target product from the biomass or culture liquid.
5. Standardization: formulating the obtained substance into its final dosage form.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Genetic engineering methods in creating recombinant strains
• Specifics of bioconversion and fermentation processes in bioreactors
• Cryopreservation and passaging processes of animal cell cultures
• Mechanisms of isolation and purification of the target product from the culture liquid
• Features of industrial cultivation of plant cells (using ginseng as an example)

Other topics in the «Biotechnology. Genetic Engineering» section

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