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Microbiology

Course developers

Replaced course

LauZ3186 [GLAU3186] Microbiology

Course abstract

Microbiology - a science that studies the morphology, biochemistry, physiology, growth, development, variability and heredity of microorganisms. In the course of microbiology students learn the most important physiological processes of microorganisms, the structure of the cell. Students learn the systematics and identification methods of bacteria, microscopic fungi. Structure and functions of viruses. The role of microorganisms in the geochemical cycle of nutrients, as well as their interaction with plants and animals.
Course Objective: To introduce students to the role of microorganisms in agriculture, promoting understanding of microbiological processes that affect soil fertility, the interaction of microorganisms with plants and animals, food safety and environmental sustainability. The course develops skills to analyse microbiological data, apply knowledge in agricultural practice and evaluate the potential of microorganisms in biotechnology and sustainable production.

Learning outcomes and their assessment

Knowledge about the diversity of microorganisms and their biology. Interaction of microorganisms with plants, animals and the environment. Impact of microbiological processes on agricultural production and application of microorganisms in agroenvironment.
Skills to carry out microbiological analyzes and to recognize main groups of microorganisms, to evaluate their activity.
Competencies.
Students are able to distinguish the most important groups of microorganisms - practical works.
Ability to evaluate the influence of environmental factors on the viability and activity of microorganisms - practical work.
Knows methods of analysis of microorganisms - laboratory works.
During the seminars students present the results of laboratory work and are able to explain them.
During the semester, students write tests to demonstrate competence in:
- differences in cell structure and physiological processes between main groups of micro-organisms;
- methods for the assessment of the diversity and activity of micro-organisms;
- the interaction between environmental factors and organisms affecting the distribution and diversity of micro-organisms in the agroenvironment;
- the role of microorganisms in elemental cycling and transformation, paying particular attention to carbon, nitrogen and phosphorus;
- the importance of microbiological processes in different areas of agricultural production;
- the use of microorganisms in agriculture.

Students' independent work summarizing the results obtained in laboratory works, understanding and explaining them. Ability to compare obtained results with literature data.

Course Content(Calendar)

I. Theoretical lectures.
1. Structure and function of the microorganisms cell.
1.1 Introduction to a brief history of microbiology. 0.5 h
1.2 The prokaryotic cell. Component the cell wall, the plasma membrane, capsules and slime layers. Gram positive and Gram negative bacteria. The formation of the endospore. The bacterial motility. 1.0 h
1.3. Microbial genetics: general principles, recombination, plasmids, conjugation, transformation and transduction. Use of microorganisms in the biotechnology. 1.0 h
1.4. Microbial taxonomy. Taxonomic criteria, classification, nomenclature, identification of microorganism. Physiological and biochemical methods for studying microorganisms and their function. Characterization of the most important groups of bacteria. 1.0 h
1.5. Characteristics, and ecological roles in soil of fungi and eukaryotic algae. Fungus-like protists. 1.0 h
1.6. Classification and characterization of the most important groups of Fungi (Chytridiomycota, Glomeromycota, Zygomycota, Ascomycota, and Basidiomycota). Eukaryotic Algae. 1.0 h
1.7. Viruses.1.0 h
1.8 Microbial metabolism: catabolism and the generation of energy. The aerobic and anaerobic respiration, fermentations. Anabolism. The metabolism regulation-control of enzyme activity. Photosynthesis: oxygenic and anoxygenic. Secondary metabolism, and antibiotic production. 1.0 h
1.9 Microbial nutrition and growth. Substrate utilization. Autochthony and zymogeny, oligotrophy, copiotrophy, and the r–K continuum. Carbon cycling and formation of soil organic matter. Composition and turnover of C inputs to soil. Plant cell wall carbohydrates, proteins and secondary compounds. Roots and Root exudates.1.5 h
1.10. Soil organic matter. Formation of soil organic matter. 0.5 h
1.11. Nitrogen transformations. Nitrogen Mineralization and Immobilization. Nitrification. Denitrification. Environmental controls of nitrogen transformations. Biological N inputs. Biological nitrogen fixation. Free-living N2-fixing bacteria. Associative N2-Fixing Bacteria. Phototrophic Bacteria. Symbiotic N2-Fixing associations between legumes and rhizobia. 1.5 h
1.12. Microorganisms in the soil biogeochemical cycling of inorganic nutrients and metals. The soil phosphorus and sulphur cycles. Micronutrient and trace metal cycling in soil. 1.0 h
2. Main functioning and application of microorganisms in the agroenvironment.
2.1. Interactions among plant and microorganisms. Environmental factors affecting interactions. Interactions among microorganisms and animals. Rumen microbiology. 1.0 h
2.2. Crop rotations and green manures. Composting. Use of synthetic and natural compounds to modify soil organisms’ communities or functions. Management of native and introduced microorganisms. Biotechnology of BNF. Managing microbial populations as agents of biological control. 1.0 h
2.3. Microbiology of animal feeds. Microorganisms in the production, preservation of agricultural products. 1.0 h
2.4. Importance of the microorganisms in the environmental biotechnology. 1.0 h

II. Laboratory works (16 h)
1) Microbiological methods used for the study of microorganisms. Laboratory equipment used for the study of microorganisms. 2 h;
2) Preparation of samples of bacteria, microscopic fungi and microscopy. 2 h.
3) Methods of staining microorganisms 4 h
4) Control of microorganisms by physical means: temperature, filtration. 4 h
5) Use of selective media for the isolation of microorganisms. 2 h.
6) Evaluation of microbial growth, isolation of pure cultures. Preservation and testing of pure cultures. 2 h

Practicals/Seminars 24 h.
Methods of cultivating microorganisms. Principles of selecting a nutrient medium;
Structure of bacterial and fungal cells. Microscopy;
Methods of limiting the activity of microorganisms. Sterilization methods; Interaction of different groups of microorganisms;
Interaction of microorganisms and plants;
Role of microorganisms in environmental bioremediation;
Microorganisms in food and feed.
In the study of agriculturally important microorganisms:
- microorganisms as environmental components, nutrient cycling processes;
- interaction of microorganisms; - interaction of microorganisms and plants;
- application of microorganisms in bioremediation;

- microorganisms in the production and preservation of agricultural products.

Requirements for awarding credit points

To complete the course, the student must meet the following requirements:
• Successfully pass the midterm tests (4), which account for 80% of the total grade.
• Pass the final exam, which accounts for 20% of the total grade.
• Attend all laboratory and practical classes.

• Actively participate in seminars, where the results of laboratory work are analyzed and presented.

Description of the organization and tasks of students’ independent work

Independent work 79 h.
During the course each student attend laboratory works
Prepare the reports of laboratory works and explain the obtained results. Independent work in preparation for tests

Criteria for Evaluating Learning Outcomes

The evaluation of final grade consists of midterm and final test results and evaluation of the results of the practical work.

Compulsory reading

1. Microbiology for Sustainable Agriculture, Soil Health, and Environmental Protection. Edited by D. K. Verma. Oakville, ON; Waretown, NJ: Apple Academic Press, 2019. 400 p.
2. Soil microbiology. R. L. Tate. New York: Wiley & Sons, 1995. 398 p.
3. Mikrobioloģija. V. Klāsens, V. Šteinberga. Rīga : Zvaigzne, 1987, 192.lpp.
4. Pārtikas mikrobioloģija. V. Nikolajeva , LU Akadēmiskais apgāds, 2011, 92.lpp.

5. Microbiology: principles and explorations / Jacquelyn G. Black; contributor, Laura J. Black. 8th ed., Wiley Chichester: John Wiley & Sons [distributor], 2013.

Further reading

Environmental microbiology. Ed. R. M. Maier, I L. Pepper, C. P. Gerba. 2nd ed. Burlington ... [ect.]: Elsevier/Academic Press, 2009. 598 p.

Periodicals and other sources

Žurnāls:
- Microbiology / Society for General Microbiology;
- Frontiers in Microbiology;
- Applied Soil Ecology.

Notes

Bachelor study programme “Sustainable Agriculture”, with specialization Sustainable plant production, 2nd semester, in full-time studies