12. Alternative therapies

Question 1

what are the three diseases yersinia pests is responsible for

Answer 1

pneumonic plague
bubonic plague
septicaemic plague

Question 2

what bacteria is commonly found in uncooked chicken

Answer 2

campylobacter jejuni

Question 3

why is campylobacter jejuni seasonal

Answer 3

it coincides with barbecue season, where more people consume raw chicken

Question 4

what is a bacteriophage

Answer 4

a virus that infects bacteria

Question 5

where are bacteriophages commonly found

Answer 5

sea water

Question 6

what % of marine bacteria may be infected by phages

Answer 6

70%

Question 7

describe the structure of a bacteriophage

Answer 7

helical sheath which attaches and injects nuclear material into the cell

tail spikes and base plate used for attachment

capsid varies in size

Question 8

what type of bacteria can phage attack

Answer 8

both gram positive and negative

Question 9

what two lifestyles can a phage adopt

Answer 9

lytic cycle

lysogenic cycle

Question 10

what is the difference between a lytic and lysogenic cycle of a phage

Answer 10

lytic phage’s burst the cell releasing phage copies into the environment

lysogenic phage’s integrate their DNA into the bacterial chromosome which replicates and is passed into daughter cells

Question 11

what type of phage is used in treatment

Answer 11

lytic lifecycle phage

Question 12

what can we use phage therapy for (2)

Answer 12

food safety - removing pathogens from uncooked food

drive microbiota towards a certain composition

Question 13

how can phages help ease antibiotic pressure

Answer 13

by coupling phage therapy with antibiotic treatment

Question 14

what are medicinal leaches used for

Answer 14

restoring blood supply following complicated surgery

Question 15

what are medicinal maggots used for

Answer 15

destroy necrotic tissue on wounds, whilst depositing ammonia to sterilise the wound

Question 16

how can we collect phages

Answer 16

collect local samples of water that contain the phage, or extracting them from corpses

then centrifuge the sample to separate the phage from the bacterial pellet

Question 17

2 advantages of phage therapy

Answer 17

phage stops reproducing once the target bacteria are destroyed

evolution drives the rapid emergence of new phages = destroy resistant bacteria

Question 18

2 disadvantages of phage therapy

Answer 18

the phage must reach the site of bacteria, however phages don’t have enough reach as antibiotics

phage must be tested in a lab before its applied, less suitable for urgent cases

Question 19

describe the case study where phages where used to treat a 53 yr old with a venous leg ulcer

Answer 19

administered phage cocktail = rapid closure of the wound, pain was relieved over 48 hrs. wound healed rapidly within 12 weeks

Question 20

describe the properties of Manuka honey

Answer 20

anti-microbial
used in wound treatment
effective against 80 microorganisms

Question 21

describe the properties of new teixobactin

Answer 21

new antibiotic

• active against Gram-positive only bacteria
• effective at low dose
• affects cell wall synthesis
• not yet approved