title: Microarray testing for the presence of toxic algae monitoring programme in Galicia (NW Spain).
abstract: Rapid and reliable detection of harmful algae in coastal areas and shellfish farms is an important requirement of monitoring programmes. Monitoring of toxic algae by means of traditional methods, i.e., light microscopy, can be time consuming when many samples have to be routinely analysed. Reliable species identification requires expensive equipment and trained personnel to carry out the analyses. However, all techniques for the monitoring of harmful algae usually require transportation of samples to specialised laboratories. In many monitoring laboratories, results are usually obtained within five working days after receiving the sample and therefore preventative measures are not always possible. Molecular technologies are rapidly improving the detection of phytoplankton and their toxins and the speed at which the results can be obtained. Assays are based on the discrimination of the genetic differences of the different species and species-specific probes can be designed. Such probes have been adapted to a microarray or phylochip format and assessed in several EU monitoring sites. Microarray results are presented for 1 year of field samples validated with cell counts from concentrated samples taken during toxic events from the weekly sampling of the Galician Monitoring Programme done by INTECMAR. The Galician monitoring laboratory does their own counting and their results are posted on their web site within 24 h. There was good correlation between cells present and microarray signals. In the few cases of false negatives, these can be attributed to poor RNA extraction of the target species, viz. Prorocentrum or Dinophysis. Where potential false positives were encountered, the smaller volume taken for cell counts as compared to the upto 300 times more volume taken for RNA extraction for the microarray is likely the cause for these differences, making the microarray more sensitive. The microarray was able to provide better species resolution in Alexandrium and Pseudo-nitzschia. In all cases, the toxins recovered by the toxin array were matched by target species in the array or in the cell counts.
authors: Department of Biology, University of Oslo, P.O. Box 1066, Blindern, 0316, Oslo, Norway.
authors: Simon M
authors: SM
authors: Dittami
authors: Yolanda
authors: Y
authors: Pazos
authors: Melchor
authors: M
authors: Laspra
authors: Linda K
authors: LK
authors: Medlin
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000706:statistics & numerical data; D004141:Dinoflagellida / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D004784:Environmental Monitoring / Q000379:methods*; D008387:Marine Toxins / Q000032:analysis; D058086:Microalgae / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D020411:Oligonucleotide Array Sequence Analysis; D010839:Phytoplankton / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D012758:Shellfish / Q000032:analysis; D013030:Spain; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D008387:Marine Toxins; D014874:Water Pollutants, Chemical
references: Nucleic Acids Res. 2004 Feb 25;32(4):1363-71
references: 14985472
references: J Eukaryot Microbiol. 2000 Jan-Feb;47(1):76-84
references: 10651300
references: Environ Sci Pollut Res Int. 2013 Oct;20(10):6808-15
references: 22767354
references: FEMS Microbiol Lett. 2005 Apr 15;245(2):271-8
references: 15837382
references: Appl Environ Microbiol. 2003 Mar;69(3):1397-407
references: 12620822
references: Biosens Bioelectron. 2007 Apr 15;22(9-10):2132-7
references: 17084071
references: Toxicon. 2001 Aug;39(8):1101-32
references: 11306122
references: Environ Sci Pollut Res Int. 2013 Oct;20(10):6794-807
references: 23250726
references: Appl Environ Microbiol. 2009 Oct;75(19):6258-67
references: 19684169
references: J Phycol. 2006 Dec 1;42(6):1333-1348
references: 20411032
references: Appl Environ Microbiol. 1993 May;59(5):1647-55
references: 8517756
references: Biosens Bioelectron. 2006 Dec 15;22(5):752-8
references: 16635568
references: Protist. 2002 Sep;153(3):223-38
references: 12389812
references: J Microbiol Methods. 2011 Feb;84(2):234-42
references: 21138747
references: Microb Ecol. 2007 Apr;53(3):371-83
references: 17334858
references: Nature. 2001 Feb 1;409(6820):607-10
references: 11214317
references: Mol Ecol Resour. 2008 Jan;8(1):99-102
references: 21585726
references: J Microbiol Methods. 2001 Dec;47(3):257-72
references: 11714516