Microbiology and Hygiene

A.Y. 2023/2024
8
Max ECTS
80
Overall hours
SSD
BIO/19
Language
Italian
Learning objectives
The purpose of the teaching of the theoretical part is that the participants acquire basic knowledge on microorganisms and understand the relationships between the structure and the biological activity, especially the pathogenic one; acquire basic knowledge on the main aspects of hygiene with particular attention to the epidemiology and prophylaxis of infectious diseases
The aim of the teaching of the practical part is that the participants learn some basic techniques as well as the use of the basic equipment of the microbiological laboratory
Expected learning outcomes
At the end of the theoretical teaching the student will have specifically acquired an understanding of the essential structural and functional differences between viruses and bacteria and consequently will have acquired an understanding of the differences in medical intervention in infections caused by viruses and infections caused by bacteria.
At the end of the practical teaching the student will be able to apply some basic methods of the microbiological laboratory and in particular will have understood the application versatility of the methods based on bacterial growth in microbiological analyzes
Single course

This course can be attended as a single course.

Course syllabus and organization

Single session

Responsible
Lesson period
Second semester
Course syllabus
MICROBIOLOGY

Bacteriology
Structure and function of the cell. Comparison among: Archaea, Bacteria, Eucarya.

Observation of microorganisms
Simple and differential staining. Fluorescent staining. Staining with specific probes. Optical and electronic microscopy.

Morphological features of the prokaryotic cell. Cytoplasmic membrane, structure and function. Bacterial transport systems. Cell wall of prokaryotes. Peptidoglycan biosynthesis. Outer membrane of Gram-negative bacteria. Capsules. Flagella and bacterial motility. Surface structure for adhesion: pili. The nucleoid. Structure and organization of bacterial chromosome. Cytoplasm. Ribosomes. Cell inclusions. Endospores.

Microbial growth and microbial growth control. Principles of microbial nutrition.
Binary fission; clonal growth (clone and colony); exponential growth;
duplication time; growth curve of the bacterial population.
Quantification of the bacterial population: total count and vital count; direct count and indirect count.
Bacterial culture. Culture media. Chemical and physical parameters that influence bacterial growth.

Metabolism.
Bacterial nutrition types.
Primary metabolism. Fermentation and substrate level phosphorylation. Aerobic and anaerobic respiration. Chemiolithotrophy

Bacterial genetics
The nucleoid. Structure and organization of bacterial chromosome. Ribosomes and polysomes. Plasmids. Replication, transcription and translation.
Mutations
Types of mutations. Parental and mutant bacterial strains
Gene transfer: transformation, conjugation, transduction.

Controlling microbial growth
Methods for sterilization. Disinfectants and antiseptics. Antibiotics. Structure and mechanisms of action. Minimal inhibitory concentration (MIC). Overview on resistance mechanisms.

Host-pathogen interaction
The human microbiota. Virulence factors and pathogenesis.

Virology
Introduction to Virology: what is a virus? Structure and classification of viruses. The Baltimore classification. Laboratory methods to study the infectious cycle. Biocontainment laboratories (BSL1 to BSL4).

Viral replication cycles. Attachment and entry. Gene expression and genome replication. Assembly and egress.

Virus-host interaction and mechanisms of pathogenesis.

Antiviral drugs: structure, mechanism of action and resistance.

HYGIENE

Introduction to Hygiene. Definitions of health and diseases. Public health. Demographic studies and epidemiology.
Preventive medicine and promotion of health. Primary, secondary and tertiary prevention. Mass screening campaigns. Oncological screening programs in Italy.
Epidemiology of infectious diseases. The epidemiological transition. The chain of infection. Sources and reservoirs of infection. Modes of transmission. Patterns of infectious disease occurence: endemics, epidemics and pandemics.
General prophylaxis of infectious disease: notification, quarantines, diagnostics, surveillance, epidemiologic survey, disinfection, disinfestation, sterilization.
Specific prophylaxis of infectious disease: active vs. passive immunization. Vaccines and vaccinations. Classical (attenuated, inactivated, subunit vaccines, anatoxins) and recombinant vaccines. Next generation vaccines: viral vectors and mRNA vaccines.


LABORATORY EXERCISES

Quantification of bacterial suspension
Sensitivity test
Gram staining
Transformation of E. coli
Isolation and growth of single E. coli colonies
Plasmid extraction from E. coli
Viral titer from biological samples
Prerequisites for admission
For lectures, basic notions of general biology, human anatomy and general chemistry are required. For laboratory activities, knowledge of concentration formulas (molarity, percentage, weight/volume), dilutions and equivalences (transition from mM to microM, from L to mL to microL, from g to mg to microg) is required.
Teaching methods
Lectures and laboratory activities
Teaching Resources
Slides of the course uploaded on Ariel website
-E. Galli, G. Dehò. Biologia dei Microrganismi Casa Editrice Ambrosiana (2018)
-M.T. Madigan, J.M. Martinko, K.S. Bender, D.H. Buckley, D.A. Stahl. Brock. Biologia dei microrganismi. Microbiologia generale, ambientale e industriale. Ed. Pearson (2016)
-N.J. DImmock, A. J. Easton e K. N. Leppard. Introduzione alla Virologia Moderna. Casa Editrice Ambrosiana, 7a edizione (2007)
-A. Amendola et al. Igiene e patologia. Zanichelli, 2a edizione (2020)
Assessment methods and Criteria
At the end of the laboratory activities there will be a verification test which consists of a written test of 15 true/false questions, lasting 30 minutes, concerning the activities performed in the laboratory. Each question is worth one point. Based on the score obtained, it is possible to get up to a maximum of two scores to be added to the exam grade.
The exam consists of a written test lasting one and a half hours and consists of 30 multiple choice questions with 4 answers for each question with only one true answer. The questions concern the whole program, both for the microbiology part and for the hygiene part. Final score is the sum of scores obtained in the different parts of the exam. The evaluation is in thirtieths.
BIO/19 - MICROBIOLOGY - University credits: 8
Single bench laboratory practical: 32 hours
Lessons: 48 hours
Educational website(s)
Professor(s)
Reception:
Upon request
INGM, via Francesco Sforza 35, or DiSFeB, via Balzaretti 9, Milano
Reception:
by appointment
INGM, via Francesco Sforza 35 o DiSFeB, via Balzaretti 9, Milano
Reception:
By email appointment
Via Balzaretti, 9. 4th floor