20410230 - MICROBIOLOGIA GENERALE

The Unit “Virology and antimicrobial immunity” of the course of General Microbiology aims to provide the basic principles of antimicrobial immunity and of structure, function and evolution of viruses. The knowledge and skills acquired during this course will represent a framework for the understanding of the whole topic and of their impact on human health and the environment.
Students who have passed the exam will know and understand (acquired knowledge) (i) structural and functional diversity of viruses, (ii) main modality of their replication, (iii) mechanisms responsible for their evolution (iv) methods and strategies for their control (v) examples of their interaction with the host; (vi) basic principles of antimicrobial immunity.
Students who have passed the exam will be able to (acquired skills) (i) understand and analyse basic test regarding the field (ii) critically analyse issues related to evolution and diffusion of viruses and to antimicrobial immunity (iii) identify and develop key themes to build educational paths in microbiology.

The module of Bacteriology of the course of General Microbiology aims to provide the basic principles of structure, function and evolution of microbial cells, with particular regard to bacterial cells. The knowledge and skills acquired during this course will represent a framework for the study of the biotechnological applications of microorganisms and for the analysis of their impact on human health and the environment.
Students who have passed the exam will know and understand (acquired knowledge) (i) the structural and functional diversity which is present in the microbial world, (ii) the mechanisms responsible for the structure and functioning of bacterial cells, (iii) the mechanisms responsible for the evolution of bacterial species, (iv) the structure and life cycles of bacterial viruses (bacteriophages), (v) the methods and strategies for the control of microbial growth.
Students who have passed the exam will be also able to (acquired skills) (i) understand and analyse bacteriological and microbiological data, (ii) critically analyse the issues related to the evolution and diffusion of multi-resistant antibiotic bacteria, (iii) understand the experimental approaches for the study and exploitation of bacteria for biotechnological and environmental purposes, (iv) identify and develop key themes to build educational paths in microbiology.
teacher profile | teaching materials

Programme

BACTERIOLOGY UNIT

Introduction to and history of Microbiology
Functional diversity and distribution of microorganisms, main discoveries in the microbiology field, present and future biotechnological applications of microorganisms.

Structure and functions of bacterial cells
Structure of the prokaryotic cell. Cell division: binary fission. Cytoplasm, cytoplasmic inclusions and sub-cellular organelles. Cytoplasmic membrane and cell wall in Bacteria and Archaea. Mechanisms involved in protein secretion and cell wall biogenesis. Surface appendages: flagella and pili. Bacterial motility and chemotaxis. Cell differentiation in bacteria and sporulation. Microbial communities: biofilms. Bacterial metabolism: chemoorganotrophs, chemolithotrophs and phototrophs. Bacterial cultures and methods for bacterial cell count. Antibiotics: activity and mechanisms of action. Evolution and mechanisms of antibiotic resistance.

Bacterial genetics and regulation of gene expression
Structure of the bacterial genome. Operons. Pangenome of bacterial species. Mobile genetic elements: plasmids and transposable elements. Horizontal gene transfer: transformation, conjugation, transduction. Structure-function of bacterial RNA polymerase. Transcriptional and post-transcriptional regulation of gene expression. Examples of global regulators: catabolite repression and quorum sensing.

Principles of bacterial taxonomy
The concept of bacterial species. Bacterial identification: culture- and molecular-based approaches. Molecular clocks and phylogenetic analysis. Characterization of complex microbial communities.

Laboratory practice
- Gram staining
- Viable cell count by plating assays
- Determination of the minimum inhibitory concentration and minimum bactericidal concentration of antibiotics
- Antibiogram (Kirby-Bauer assays)

Core Documentation

Madigan, Martinko. Brock. Biology of microorganisms. Pearson.

The textbook must be integrated with the slides of the lessons and the protocols of the exercises that will be provided by the teacher.

Type of delivery of the course

The course is structured in lectures and laboratory exercises. In particular, 46 hours of teaching are planned for the Bacteriology unit, with 36 hours of lectures and 10 hours of laboratory exercises (with three repetitions). Frontal lessons are held weekly in the classroom and the teaching occurs through the use of power-point presentations. Attendance at lessons is not mandatory but strongly recommended.

Type of evaluation

The exam is aimed at verifying the level of knowledge and comprehension of the topics of the program and the reasoning skills developed by the student. The evaluation is expressed in thirtieths (minimum mark 18/30, maximum mark 30/30 cum laude). The exam consists of a written test (optional) and an oral examination. The written test includes both open and closed questions on the topics covered during lectures and laboratory exercises. Open questions are evaluated for accuracy, completeness of content as well as synthesis and elaboration skills. If the mark of the written exam is at least 18/30, the oral exam will be mainly focused on the discussion about the tests and the main mistakes made by the student. If the student does not pass or accept the mark of the written test, or if the student does not take the written test, the oral exam will cover all the topics of the course. Property of language, clarity of exposition, acquired knowledge and ability to make connections between the different topics are evaluated during the oral examination. Overall, the exam aims to verify the achievement of the objectives in terms of knowledge and comprehension of the topics, as well as communication skills.

teacher profile | teaching materials

Programme

What are viruses and how do they replicate. Types of capsids and their function, types of genomes and phases of the viral multiplication cycle.
Definition of viral species and quasi-species and introduction to viral taxonomy
Acute, latent and persistent infections: definition and examples
David Baltimore's breakdown of viruses into 7 replication classes and the differences between classes.
Virus titration, cultivation and isolation methodologies
Attack mechanisms and viral penetration
The size of the viral genomes and their distinctive characteristics compared to the cellular genomes
Genetic variability in DNA and RNA viruses in comparison.
Replication cycle of some DNA phages (T4, lambda, φX174 and M13 as examples of Baltimore class I and II phages). The host's restriction against phage infections.
Both phages and animal viruses can transduce cellular genes with different mechanisms.
SV40 and human papillomaviruses, two small dsDNA animal viruses of Baltimore class I viruses): replication cycle, definition of host and permissive and non-permissive cells, promotion of oncogenesis.
Introduction to innate antimicrobial immunity and PAMPs, induction of type I interferons and introduction to their mechanism of action.
Antibodies: structure and function, monoclonal and polyclonal antibodies, use in microbiology
The definition of serotype and genotype and methods used to define them (neutralization test and genome sequencing)
Notes on the humoral and cellular adaptive immune response against microbial infections: role of B, Tc and Th lymphocytes; differences between primary and secondary immune response to infections.
Replicative cycle of three different positive ssRNA viruses in comparison (i.e., poliovirus, hepatitis C virus, phage Qβ or MS2) as examples of Baltimore class IV viruses). Introduction to coronaviruses and the viral pandemics of the XIX and XX centuries.
The Vesicular Stomatitis Virus and the flu virus in comparison (examples of Baltimore class V viruses)
Retroviruses as example of Baltimore class VI viruses: oncogenic retroviruses and the AIDS virus. Why the hepatitis B virus (Baltimore class VII) is defined an upside down retrovirus.
Antimicrobial vaccines (the story: Jenner and smallpox, Pasteur and rabies; examples of anti-viral and antibacterial vaccines used today: anti-tetanus, -polio, -pertussis, -hepatitis B, -HPV, -flu)
practical laboratory exercises:
1. introduction to animal cell cultures
2. hemagglutination test as a titration or serological identification test



Core Documentation

Use PDF files of lessons and exercise present in the Moodle platform and the following textbook: N. J. Dimmock, A. J. Easton, K. N. Leppard - Introduction to Modern Virology - Seventh edition 2016 -Wiley Blackwell - ISBN 978-1-119-97810-7 or later editions.
Consult the web site viralzone.expasy.org.


Type of delivery of the course

The course is structured in lectures and laboratory exercises. In particular, 29 hours of teaching are planned for the “Virology and antimicrobial immunity” Unit, with 24 hours of lectures and 5 hours of laboratory exercise (with three/four repetitions). Frontal lessons are held weekly in the classroom and the teaching occurs using power-point presentations. The two different practical exercises are carried out in the biological didactic laboratories on different days, dividing the students into groups compatible with the manual skills and management of the group and repeating each individual exercise several times based on the total number of students. Attendance at lessons and exercises are not mandatory but strongly recommended.

Type of evaluation

The exam is aimed at verifying the level of knowledge and comprehension of the topics of the program and the reasoning skills developed by the student. The evaluation is expressed in thirtieths (minimum mark 18/30, maximum mark 30/30 cum laude). The exam consists of a written test (optional) carried out shortly after the completion of each of the two teaching units of the course and/or an oral examination. The written test includes both open and closed questions on the topics covered during lectures and laboratory exercises. Open questions are evaluated for accuracy, completeness of content as well as synthesis and elaboration skills. If the mark of the written exam is at least 18/30, the oral exam will be mainly focused on the discussion about the tests and the main mistakes made by the student. If the student does not pass or accept the mark of the written test, or if the student does not take the written test, the oral exam will cover all the topics of the course. Property of language, clarity of exposition, acquired knowledge and ability to make connections between the different topics are evaluated during the oral examination. Overall, the exam aims to verify the achievement of the objectives in terms of knowledge and comprehension of the topics, as well as communication skills. The results and procedures performed by students during the activity will be discussed on site and a final questionnaire will be administered to evaluate the understanding of the lab work. Didactic material is provided during the exercises