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Development of a short-term assay based on the evaluation of the plasma

membrane integrity of the alga Pseudokirchneriella subcapitata

(Supplementary Information - Applied Microbiology and Biotechnology)

Manuela D. Machado and Eduardo V. Soares

Author for correspondence:

Eduardo V. Soares

Address: Bioengineering

Laboratory, Chemical Engineering Department, Superior

Institute of Engineering of Porto Polytechnic Institute, Rua Dr António

Bernardino de Almeida, 431, 4200-072 Porto, Portugal;

e-mail: evs@isep.ipp.pt

Tel: 351-22-8340500

Fax: 351-22-8321159.

Fig. S1. Visualization of heat

Green. In order to permeabilize the plasma membrane, a

(65ºC, 1h) and subsequently incubated with 0.5 μmol/l SYTOX Green for 40 minutes at

25°C. Fluorescence micrograph (a); phase contrast micrograph of the s

Visualization of heat-treated cells of the alga P. subcapitata stained with SYTOX

In order to permeabilize the plasma membrane, algal cells were heat

subsequently incubated with 0.5 μmol/l SYTOX Green for 40 minutes at

Fluorescence micrograph (a); phase contrast micrograph of the same cells (b).

2

stained with SYTOX

lgal cells were heat-treated

subsequently incubated with 0.5 μmol/l SYTOX Green for 40 minutes at

ame cells (b).

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Fig. S2. The fluorescence response to increasing numbers of P. subcapitata cells

incubated with SYTOX Green. Live cells (open circles) and dead cells (closed circles)

were incubated with 0.5 μmol/l SYTOX Green for 40 minutes at 25°C. Each point

represents the mean of five fluorescence readings; standard deviations are presented

with 95% confidence limits (vertical error bars).

0

20

40

60

80

100

120

140

160

0 2 4 6 8 10

Flu

ore

scen

ce (

RF

U x

10

3)

Cell density (cells x 105/ml)