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Flashcards in Secondary metabolites 1 Deck (25)
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1
Q

when are secondary metabolites produced

A

stationary phase of growth after main growth phase has ended

2
Q

what is different about secondary metabolites and primary metabolites

A

primary metabolites have common shared paths across organisms, whereas secondary metabolites produced by an organism are specific biochemical pathways specialised to that organism

3
Q

at what growth stage are secondary/ primary produced in

A

primary - tropophase

secondary - idiophase

4
Q

3 functions of secondary metabolites

A
  • reducing competition - limiting others around
  • storage compounds - later can be broken down
  • maintains metabolism so that the organism could start growing again if it wanted to
5
Q

what are polyketides

A

structurally diverse group of organic acids, all with the same backbone

6
Q

name 3 important/common polyketides

A

doxycycline, erythromycin - antibiotics

Aflatoxin B1

7
Q

basic structure of polyketides

A

either a 2 carbon/ 3 carbon starting point, sugar side chains can be added - glycosylated

8
Q

What are polyketides primarily formed by

A

fungi, and actinomycete bacteria - filamentous - look like fungi

9
Q

what are some other examples of benefits of polyketides

A

cholersterol-lowering, immunosuppressants, anti-cancer/parasitic/fungal

10
Q

where are aflatoxins found

A

produced from microorganisms found on corn

11
Q

what is a protein domain

A

specialised enzymatic production, new proteins evolve by bringing together new domains, they fold independently of the protein

12
Q

what is a protein module

A

1-6 domains coming together to carry out a function

13
Q

what are PKS

A

polyketide synthase enzymes - the 2c starting unit loads onto the enzyme and moves through it adding on 2 carbons, one being lost as CO2 - gradually gets bigger and bigger polyketide

14
Q

what are the two types of PKS enzymes

A

type 1 - form more complex PKs, they are a very large single protein with multiple domains
type 2 - form simple PKs, they are several different polypeptides each with a specific domain coming together as one - bound together to form a quaternary protein

15
Q

what antibiotoc is used for acne

A

arythromycin

16
Q

what are statins and how do they work

A

a drug that blocks the enzyme HMG - CoA in the liver that produces cholesterol - acts as a competitive inhibitor blocking production

17
Q

what is gene localisation

A

genes involved with other processing are often clustered within the same enzyme in the same location of the genome

18
Q

what is amphoteraicin

A

an anti-fungal drug used to treat thrush

19
Q

how does amopheteraicin work

A

humans have cholesterol to strengthen the membrane, whereas fungus have ergosterol - the drugs target the ergosterol - cell leakage - then death

20
Q

why are fungal infections so hard to treat

A

because human cells and fungal cells are very similar - both eukaryotes - drugs can easily harm humans as well as the fungal cells

21
Q

what is griseofulvin

A

anti-fungal drug used to treat ringworm and nail infections

22
Q

how does griseofulvin work

A

prevents the assembly of fungus microtubules and mitosis

23
Q

what is doxorubicin

A

anti-tumour drug - used in cancer chemotherapy - fermentation of GM engineered strain of Streptomyces

24
Q

how does doxorubicin work, and what are the problems

A

stops DNA replication, could interfere with normal cell growth

25
Q

what do avermectins treat

A

blocks nerve transmission in nematode/arthropod/ parasitic infections