Teaching plan of bilingual teaching
双语教学教案
Gannan Medical College
Department of pathogenic Biology
Teacher
（教师）
Date
（日期）
Grade
（年级）
Speciality
专业
Lecture type
(授课类型)
Clinical medical
(临床医学)
Subject
（课程）
chapters and sections
(授课章节)
Chapter 5 Genetics and Variation
Objective and request
教学目的和要求
1.
2.
3.
4.
5.
Emphasis and difficulty
授课重点、难点
Reference teaching material
参考教材
Teaching aid
媒体与教具
Theory Course
(理论课)
Class hour
（学时）
Medical Microbiology
医学微生物学
Master the characteisticrs of plasmid.
Master the mechanism of mutation and gene transfer of bacteria
Master the interrelation between phage and bacteria
Understand the.size, shape and structure of phage
Understand the characteristics of Viral Genetics.
1. The interrelation between phage and bacteria
2. The mechanism of mutation and gene transfer of bacteria
1．周正任主编.《医学微生物学》第 6 版
2．Medical microbiology(21 edition, Jawetz, Melnick, and Adelberg)
Powerpoint
Teach contents（教学内容）
Chapter 5
Genetics and Variation
Section I Bacterial inheritance and variation
Concept:
(1) heredity : general stability on “likeness” in the characteristics of progeny and parent.
(2) variation: the difference between progeny and parent
Heritable variation: genetic substance changes .
nonberitable variation : enviroment changes
I. variation examples.
1.shape and structure variation
2.colony variation
smooth colony
rough colony
3. virulence variation, vaccine
BCG: Bacilli of calmetter-Gueria ;230 passages, 13 years.
4. Resistance variation
1
2 hours
II. Genetic substance
1. chromosome
consists of a circular double strand DNA molecular, control bacterial life without introne.
2. Plasmid
Extrochromosomal genetic substance. Circle double strand DNA
（1）autonomous replication
binding to chromosome —episome
（2）contral most of auxiliary functions of bacterial cell
Antibiotic resistance——R plasmid .
production of fimbriae ——F plasmid
bacteriocin——E. coli col. plasmid.
（3）dispensable, it can be lost .
（4）tranfer from a bacteria to another
（5）Incompatibility and compatibility.
3. bacteriophage.
Bacteriophage
Infecting bacterial virus
(1) viral common properties
smallest ,simple structure , DNA/RNA, parasite in living cell
(2) widespread existence
(3) high host –specific parasitism
(I.) biological properties
1. Shape and structure
Seen by EM: Tadpol , microsphere slim rod
Structure:
head
core: DNA/RNA
Capsid: protein coat
Tail: pipe-like, collar, base plate, tail fib
(II). Interrelation between phage and bacteria
1. Virulent phage. Reproduction and lyzing Bacteria, which can replicate in cell and released in lysis of B .
2. lysogenic phage. infected bacterial phage doesn’t replicate it’s gene ,integrated with bacterial DNA,
its replication is associated with bacterial DNA
lysogenic phage (temperate phage)
lysogenec bacteria
prophage : The DNA of temperate phage integrated into bacterial DNA.
4.transposon:
transposable elements
insertion sequence
transposon
III. Mechanism of bacterial variation:
1. Mutation
(1) concept: a stable heritable change of acterial gene ,
(2) type of mutation
2
2. genetic transfer and recombination
1) transformation
recipient B. takes up exogenous DNA of donor B.
2) transduction .
donor bacterial DNA is transfered to recipient bacterial by phage .
3) conjuqation
bacterial DNA is transferred from donor bacteria to recipient bacteria by F pilus.
4) lysogenic conversion
5) protoplast fusion
III. Medical application
1. Bacterial indentification
2. prevention treatment of diseases. Eg . vaccine
3. screening potential carcinogen . Ames test
4. genetic engineering
Section II Viral Genetics
The nature of the viral genome (RNA or DNA; segmented or nonsegmented) plays an important role in the
genetics of the virus.
1. Mutations:
----permanent changes in sequence of nucleotides in nucleic acid.
----types of utation:
Mutants can be point mutants (one base replaced by another) or insertion/deletion mutants.
---- origion
(1) Spontaneous mutations
(2) Mutations that are induced by physical or chemical means
----examples of Mutant
2. Recombination and reassortment:
3. Integration: viral genome insert into host cell genome .
4. Complementation:
5. Phenotypic mixing:
question
思考题
What are the mechanisms of transformation, conjugation, transduction, and lysogenic
conversion?
3