GENERAL MICROBIOLOGY

Degree course: 
Corso di First cycle degree in BIOLOGICAL SCIENCES
Academyc year when starting the degree: 
2015/2016
Year: 
3
Academyc year when helding the course: 
2017/2018
Course type: 
Compulsory subjects, characteristic of the class
Credits: 
9
Period: 
First Semester
Standard lectures hours: 
78
Detail of lecture’s hours: 
Lesson (64 hours), Exercise (6 hours), Laboratory (8 hours)
Requirements: 

Propedeuticity: Biochemistry. Some notions of Genetics (mutations, selection methods, recombination processes in prokaryotes) and Molecular Biology (DNA replication, transcription, translation) are also required.

The exam consists of an oral interview aimed at verifying i) the level of in-depth knowledge of microbiology fundamental notions and techniques, ii) the ability to communicate them with appropriate scientific language skills, iii) the ability to link the various topics, iv) the awareness of the different areas of application of microbiology and its implications.
Theoretical and practical exercises, although are not object of specific verification, are integral part of the exam program.

Assessment: 
Voto Finale

The course provides an overview of the microbial world, starting from the structural and functional features of microorganisms, particularly prokaryotes, to then analyze their interactions with other organisms and their role in different contexts.
The course provides the basics for a correct approach to the study of the microbial world and for understanding the relevance of microorganisms in Life Sciences.
At the end of the course, the student must have acquired theoretical and operational skills related to the biology of microorganisms. Knowledge: The student will be required to know, with an appropriate level of in-depth knowledge, the topics discussed in the attached program and to be able to communicate them with a scientifically correct language. The student will be also required to be able to link the different topics dealt with previously studied disciplines and to be aware of the possibilities of application and of the implications of Microbiology in different contexts. Skills: Students will have to know and be able to use basic, conventional and molecular techniques for isolation, identification and, in general, for the study of prokaryotes. It will also need to be able to design simple experiments, to analyze the data and communicate them using a scientifically correct language.

Structure and functions of prokaryotic cells. (6 h) Morphology, size, organization. Differences among Bacteria, Archaea, Eukarya. Cell wall: Gram positive, Gram negative, Archaea. Cytoplasmic membrane; transport and secretion systems. Surface structures: capsule, S layers, fimbriae and pili. Motility: flagella, random and oriented movement. Protoplast: cytoplasm, ribosomes, nucleoids, inclusion bodies.
Microbial growth. (8 h) Elemental cell composition. Nutrition diversity. Culture media: minimal and complex, selective and differential. Isolation techniques. Pure cultures. Growth of microbial populations: methods for determining biomass and cells number. Mathematical Description of Growth. Growth curve. Environmental effects on microbial growth: temperature, pH, water availability, oxygen availability. Extremophile microorganisms. Physical and chemical methods for growth control.
Energy and assimilation metabolism. (14 h) Chemotrophy. Fermentation. Aerobic respiration. Anaerobic respirations: denitrification, desulfurylation, methanogenesis, homoacetogenesis. Chemolithotrophy. Oxygenic and anoxigenic photosynthesis. Assimilative and biosynthetic metabolism. Assimilation of organic compounds. Assimilation of CO2. Nitrogen fixation and assimilation. Assimilation of sulfur and phosphorus.
Microbial classification and taxonomy. (2 h) Classification systems. Conventional and molecular methods for identification.
Element Cycles. (3 hours) Role of microorganisms in cycles of C, N, S. Overview of the degradation of natural and synthetic organic compounds in aerobic and anaerobic environments. Symbiosis.
Essential of virology. (4 h) General properties of viruses. Structure and organization of virions. Multiplication of viruses. Cultivation methods. Examples of life cycle of bacteriophages and eukaryotic viruses.
Bacterial genetics. (6 h) The microbial genomes. Chromosome, plasmid, other genetic accessories. Integrity of genetic information and generation of mutations. Types of mutants and selection systems. Horizontal gene transfer: conjugation, transformation, transduction. Evolutionary significance of genome plasticity.
Regulation of gene expression. (5 h). How bacteria perceive the environment. The various levels of regulation of cellular activities. Positive and negative transcriptional regulation of anabolic and catabolic operons. Examples of super-operonic regulation and of global regulatory network.
Differentiation. (6 h) Differentiation as an adaptive response. Endospore formation. Morphological and physiological differentiation: streptomycetes. Intercellular communication: quorum sensing. Bacterial biofilms.
Microorganism-human interactions. (6 h) Role of the body normal flora. Pathogenic bacteria: reservoirs and transmission. Concepts of pathogenicity and virulence. The virulence factors. Endotoxins. Classification and examples of exotoxin action mechanisms. General and specific host defense mechanisms: an overview.
Antibiotics. (4 h) Producer microorganisms. Classification and examples of mechanism of action of some antibiotics. Determination of bacterial sensitivity to antibiotics. Biochemical and genetic bases of bacterial resistance.
For each topic, the main groups of microorganisms concerned will be mentioned or described.
Exercises: Data processing of a vital count, generation of a growth curve and determination of descriptive parameters; use of flow charts for bacterial identification; use rDNA database.
Practical lessons: Aseptic techniques, solid and liquid cultivation, vital counts, growth media, differential stains.

Madigan et al., Brock Biologia dei microrganismi. 14° Ed. Pearson.
Dehò G., Galli E. Biologia dei microrganismi. CEA
The lesson slides are not provided because the illustrative material is taken from the texts cited.

The course includes lectures (8 CFU), calculation, design and simulation exercises (0.5 CFU), and practical lessons (0.5 CFU).
During lectures, the topic is handled with the help of classroom presentations and educational films.
Calculation and design exercises are performed in classrooms in working groups; the simulations are carried out individually in the computer labs of the teaching facility in Via Monte Generoso, each student is assigned a computer station (equipped with a PC connected to the web).
Practical lessons are carried out in the Laboratory of Experimental Biology at via Dunant 3. Each student is provided with a dossier with description and experimental protocol. Students should wear white coat, other personal protective equipment will be provided as needed. During the practical lessons, assistance will be provided by the teacher and one or more practitioners. The attendance of teaching laboratories is compulsory, absences are allowed for no more than 25% of the practical lessons.
Students with disabilities, allergies or pathologies that may be aggravated by contact with microorganisms or chemical reagents must inform the teacher in writing (even by email) before starting the practical lessons.

The teacher receives by appointment set up by e-mail. Students are required to use the institutional mail.

Professors

BARBIERI PAOLA