Question

­­­­Lecture Homework Assignment (LHA) #4

Bio 2010 Microbiology

Print Name: _________________________                                       Section # ________

Virulence Factors:

There are two classes of bacterial exotoxins that are based on their target. Identify the two classes of exotoxin and the target for each. (1/2 pt. ea.; 2 pts. Total)

Type of Exotoxin                                              Target

 

 

 

Other than exotoxins, name two virulence factors associated with bacterial pathogens. (½ pt. ea.; 1 pts. Total)

Foodborne Disease:

Differentiate between the following types of foodborne disease in terms of (1/2 pt. ea.; 3 pts. Total):

i) what is ingested; ii) relative length of incubation period; iii) relative duration of period of illness. (NOTE: For answers ii) and iii), do NOT give specific number of hours, days, etc., but rather the relative length of time compared to each other.

Intoxication:

i)

 

ii)

 

iii)

 

Foodborne infection:

i)

 

ii)

 

iii)

 

Name two pathogens (Genus & species) for each of the two types of foodborne disease. (½ pt. ea.; 2 pts. Total)

Intoxication:

1.)

2.)

Foodborne infection:

1.)

2.)

Antibiotic Resistance:

What are the two things that mankind is doing that result in increasing levels of antibiotic resistance? (Answers should be one word each.) (1/2 pt. ea.; 1 pt. Total)

1.)

2.)

Penicillin, cephalosporin, monobactams, and carbapenums all belong to the same class of antibiotics, based on a common molecular structure in each. 1.) What is the name of this chemical structure?   2.) On the basis of this molecular structure, what is the name given to the class of enzymes that cleaves it? (Hint: The term is generic to all of these enzymes. Do not provide names that only apply to a single antibiotic.)   3.) Draw a picture of this structure and only this structure, and label each atom. (1/2 pt. ea.; 1 ½ pt. Total)

1.)

2.)

               

                3.)

Penicillin inhibits what metabolic process in susceptible bacterial cells? Be specific. (Hint: This is an example of one of the five ‘mechanisms of resistance,’ of certain bacteria against certain antibiotics. It also is the basis of the Ames Test, to determine potential chemical carcinogens.) (1 pt. Total)

Viruses:

Identify, in the correct order, the steps during the replication of an enveloped animal virus. (½ pt. ea.; 3 pts. Total)

 

 

 

 

Transfer of genes from one bacterium to another may be accomplished by incorrect assembly of bacteriophage that contain gene(s) from the original host bacterium. This process is known as what? One word answer. (1 pt. Total)

 

 

What are the three ‘Golden Rules’ of genetics that also apply to viruses? (1/2 pt. ea.; 1 ½ pt. Total)

1.)

2.)

               

                3.)

Immunity: Match the Immunological Process with the best description of the Type of Immunity elicited. Each Immunological Process can be used only one time, but the Type of Immunity may be associated with more than one Immunological Process. (1/2 pt. ea.; 3 pts. Total)

Type of Immunity	Immunological Process
11. Artificially-acquired, Passive immunity	A. Complement Activation by Alternative Pathway
12. Artificially-acquired, Active immunity	B. Infectious disease
13. Naturally-acquired, Passive immunity	C. Transfer antibodies from another immune animal
14. Naturally-acquired, Active immunity	D. Vaccination
15. Non-specific immunity	E. Breastfeeding neonate
	F. Phagocytosis of complement opsonized antigen

 

Answer 1

@ Based on the target tissue, Exotoxins can be classified into 3. They are type I, II and III.

Type I Exotoxin- Example - Superantigen - Target -Cell surface receptors

Type II Exotoxin - example - Hemolysin - Target - Cell membrane

@ Other than toxins, bacterial appendages like Capsule and pili act as virulence factors.

Food borne diseases

Intoxication: i) food with toxins. no viable bacteria ii) short incubation period iii) short disease duration

Food borne infection : i) food with live bacteria ii) longer incubation period iii) longer disease duration

Intoxication 1) Staphylococcus aureus 2_ Clostridium perfringens

Food poisoning 1) Salmonella typhi 2) Vibrio cholera

Antibiotic resistance

1) Over use

2) Incomplete dose

@Penicillin, cephalosporin, monobactams, and carbapenums all belong to the same class of antibiotics, based on a common molecular structure in each. 1.) What is the name of this chemical structure?

Beta lactam ring

@ On the basis of this molecular structure, what is the name given to the class of enzymes that cleaves it?

Betalactamase

Draw the structure : picture attached at the end

@ Penicillin inhibits what metabolic process in susceptible bacterial cells?

It inhibits Cell wall synthesis. In the molecular level, penicillin inhibits transpeptidase enzyme.

@ Identify, in the correct order, the steps during the replication of an enveloped animal virus.

Attachment, Penetration, Uncoating, Biosynthesis, Assembly or Maturation, Release by budding

@ Transfer of genes from one bacterium to another may be accomplished by incorrect assembly of bacteriophage that contain gene(s) from the original host bacterium. This process is known as what?

Answer : Transduction.

@ Three golden rules of genetics

1. Law of dominance

2. Law of seggregation

3. Law of Independent assortment

@ Match the following

11. Artificially-acquired, Passive immunity - C. Transfer antibodies from another immune animal

12. Artificially-acquired, Active immunity - D. Vaccination

13. Naturally-acquired, Passive immunity - E. Breastfeeding neonate

14. Naturally-acquired, Active immunity - B. Infectious disease

15. Non-specific immunity - F. Phagocytosis of complement opsonized antigen and A. Complement Activation by Alternative Pathway