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….$CLONES$OF$MICROCYSTIS$AERUGINOSA$USING$LECTINS$

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UEA?1! lectin! seems! to! be! specific! enough! to! bind! only! to! non?toxic! M.)

aeruginosa)cells.!Figure!2!shows!the!lectin!binding!activity!observed!using!an!epi?
fluorescence!microscope.!Colonies!positive!for!lectin!binding!showed!intense!green!
fluorescence! on! the! cell! surface! (thin! arrows)! as! well! as! on! inter?cellular! matrix!
(wide!arrows)!non?toxic!M.)aeruginosa!cells.!This!procedure!is!extremely!useful!to!
identify! the! abundance! of! toxic! cells! in! a! bloom.! It! as! easy! as! collected! a! single!
water! sample! directly! from! a! bloom! and! make! a! rapid! staining! procedure! and! a!
straightforward! observation! under! an! epi?fluorescence! microscope! is! sufficient.!
With!this!experimental!procedure!we!were!able!to!successfully!separate!non!toxic!
and!toxic!M.)aeruginosa!strains!in!several!water!samples!from!different!blooms.!As!
a! rule,! a! larger! amount! of! microcystin! indicates! more! percentage! of! unmarked!
colonies!by!UEA?1!lectin.!

TOXIN STRAIN !

0.00 MaC3
0.00 MaC6
0.00 MaG15
0.00 MaM1
0.00 MaD9
0.00 MaM13
0.00 MaM14
0.00 MaG2
0.00 MaM5
0.00 MaG16
0.00 MaC4
0.00 MaG9
0.00 MaM2
0.00 MaD3
0.10 MaG6
0.09 MaG5
0.16 MaG4
0.15 MaG3
0.04 MaC1
0.05 MaM9
0.02 MaM10
0.02 MaM6
0.07 MaG7
0.07 MaM3
0.04 M11
0.09 MaM4
0.06 MaD6
0.04 MaD4
0.15 MaD2
0.11 MaD5
0.17 MaD8
0.28 MaD1
0.31 MaG8
0.33 MaD7
0.26 MaC5

Figure$ 1.B! Hierarchical! cluster! analysis! (dendrogram! using! a! binary! average! linkage).! ! (MaD?!
strains!from!a!bloom!in!Doñana!National!Park;!MaG?!strains!from!bloom!in!water!supply!reservoir!
of!El!Gergal;!MaM?!strain!from!a!bloom!in!water!supply!reservoir!of!La!Minilla.;!MaC?!strain!from!a!
bloom! in! water! supply! reservoir! of! Cuerda! del! Pozo.! Toxin! production! of! each! strain! (in! fg!
microcystin?LR!equivalent!per!cell)!is!also!summarized.!

!

In!this!study,!8!lectins!and!35!strains!from!four!M.!aeruginosa!blooms!from!
a!restricted!geographical!range!(Spain)!were!used.!Although!this!work,!to!the!best!
of! our! knowledge,! is! the! most! extensive! lectin?binding! study! performed! on! M.!
aeruginosa!(by!number!of!lectins,!strains,!blooms!and!field!samples!analysed)!is!a!
work! limited! to! M.! aeruginosa! blooms! from! Spain.! Spain! is! the! second! biggest!
European!country!(and!the!country!with!more!problems!caused!for!M.!aeruginosa!
blooms).! Important! Spanish! water! supply! enterprises! as! well! as! the! toxin!
cyanobacteria?monitoring!program!of!Doñana!National!Park!(which!support!more!
than! 85%! of! water?birds! European! biodiversity)! are! successfully! using! this!
procedure.! However,! the! Microcystis! problem! is! a! global! problem! that! implicates!

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