A resonance raman study of carotenoid susceptibility to photooxidatiom in the cyanobacterium Anacystis nidulans

269

JournalofMoIecu&rStructure,60(1980)269-272 0 Elsevler Scientific Publishing Company,Amsterdam-&Printedthe

A RESONANCE

RAMAN

PHOTOOXIDATION B.

SZALONTAI

Institute

and

OF CAROTENOID

ANACYSTIS

TO

NIDULANS

K. CSATORDAY

Research

Szeged,

SUSCEPTIBILITY

CYANOBACTERIUM

of Biophysics,

Biological H-6701

STUDY

IN THE

Netherlands

Institute

Hungarian

Center,

P.O.Box

of Plant

521,

Physiology,

Academy

of

Sciences,

Hungary

ABSTRACT Carotenoids membrane

were

proven When

structure.

to be convenient

no change

intensities

and

carotenoids

to photodestruction This

research. interaction

the

decay

Raman

was

taken

in the

Raman may

advantage

auxiliary

constant

spectra

also

constant

made

perature

of

possible

the

membrane

is

of

peak of

in membrane

phycocyanin-carotenoid

nidutans.

temperature

probes

sensitivity

During

lost

and

dependence

of the phase

nitrate

the

of the

deterioration

the determination

thylakoid

the

The

diminished.

studying

phycocyanin

from

the

a new dimension

Anacystis

pigment

calculated

offer

active

in relative

spectrum

of by

in the cyanobacterium

starvation the

positions

Raman

is detectable

value

of

resonance

of the

transition

decay tem-

as well.

INTRODUCTION In the intrinsic ized

present

as Raman

tural

basic and

during

bound

active

susceptibility The

communication

membrane

riporter

idea

of the

energetical loss

was was

organisation of the

Changes

in the pigment

as

as

the

study

light

apparatus

subsequent

about

and

niduZans

their

to follow of

were

in which were

the util-

environment-dependent

investigated. the

changes

the photosynthetic

harvesting

restoration

a study

of Anacystis

molecules

to photooxidation

partial

well

we report

carotenoids

pigment

induced of

to

the

struc-

membrane

phycocyanin

by nitrate

nitrates

in the

(ref.1).

starvation culture

(ref.2). RESULTS It was

found

that

the

resonance

enhanced

Raman

peaks

of carotenoids

270

0

3 k-c-)

- 625

clli’

3 kc-d-1160

7400 cm-' 1200

1600

1000

I

1000

Fig. 1. A topical time-dependent change In the carotenoids in Anacystis. Numbers at the Raman lapsed after illumination was started.

in

Anacystis

prolonged

and

in

the

(Flg.1)

concurred

that

excited

exposition

spectra decay.

if

there

is

in

to

case

of

Its

decay

their

laser the

absorption

1Lght

algae

constant

with

the

some

direct

(ref.2).

healthy

loss

of

The

interaction

a

single

under of

the

exponential

nitrate

starvation

fluorescence.

between

of seconds

deterioration

upon

phycocyanin

spectrum indicate

tkec)

deteriorates

follows

decreased

2000

Raman peaks

band

cm”

This

phycocyanin

result

and

caro-

tenoids. After to but

restoration

chlorophyll a part

a lower

ratio

of

efficiency

not

In

vesting

the

the

of

the

final

the

reattained

That

highly

culture in

fluoresces

excitation

(ref.2).

the

Raman

obtained slow

depleted

be

to

the

the

fluorescence

separately

energy means

effective

at

transfer

that

the

initial

newly

conformation

650

from

phycocyanin spectrum

nm

indicating

phycocyanin

synthetized of

the

to pigments

light

har-

system.

During in

can

nitrate

phycocyanin

allophycocyanin are

of

in

regeneration decay

healthy

phase alga

curves algae

reflects (Fig.2.).

of

the

whose at values

culture

final

the

value

beginning

characteristic

a

fast

component

corresponds of

appears to

the

experiment

for

the

the

decay

while

phycocyanin

271

I

0

1000

500

1500

2000

2500

t kec)

Fig. 2. Evolution of the biphasic decay of Raman-peak intensity at 1525 cm-* during regeneration of .4nacystis niduZans following readdition of nitrates. Numbers indicate hours lapsed after readdition of nitrates to the culture medium. (With the permission of Academic Press from ref.2.) We

suggest

that

to carotenoids the

slow

ciation

the

which

component with

the

fast

are

component

closely

reflects recently

in these

associated

carotenoids formed

and

decay

with

which

higher

curves

corresponds

phycocyanins

are

yield

not

while

in close

fluorescing

assophyco-

cyanins. Carotenoids brane pendent the

The which

aggreed that

in the The

phase

OC

was

cyanin

membrane

overall

proved

the phase

transition

found

state

of the mem-

to be temperature

trnsition

temperature

to be at

temperature

with

the

Raman

causes

interactron

but

as well

since

starved of the

the membrane

of Anacystis

24 OC by spin

starvation

of nitrate

determination from

the

constant

to reflect

excellently

nitrate

case

to monitor

decay

deof

membrane.

cyanin-carotenoid thylakoid

utilized Raman

able

membrane at 38

grown

The

and was

thylakoid

seen

were

as well.

not

data only

a general

niduZans

labelling

(Fig.3).

(ref.31

It can

the loosening decomposition

we observed

no phase

be

of phycoof the

transition

alga.

connection

surface

and

between the

the

removal

desintegration

of phyco-

of the mem-

272

Healthy alga

I

Nitrate starved alga r-l u

30

25

in the photosynthetic 3. Phase transrtion as reflected by Raman decay constants carotenoldsFig.

nidu2ans

brane The active

needs

authors riporter

produce on

further

actrve

u “C

membrane of Anazyst?Js of membrane bound

studies.

belleve

that

molecules

additronal

Raman

II

the degradatrve

can

be applied

lnformatlons

membrane

lnvestlgation

in various

in comparison

with

cases previous

of

Raman

and

can

studies

probes.

REFERENCES 69(1969)114-120. 1 M-M. Allen and A.J. Smith, Arch. Mlkrobiol. and K. Csatorday, Blochem. Biophyls. Res. Commun. 2 B. Szalontai 88(1979)1294-1300, 3 N. Murata, J.H. Troughton and Fork D.C., Plant. Physiol. 56(1975)508-517.