1. Morphological, toxicological and molecular characterization of a benthic Nodularia isolated from Atlantic estuarine environments.
- Author
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Lopes VR, Antunes A, Welker M, Martins RF, and Vasconcelos VM
- Subjects
- Animals, Artemia drug effects, Artemia growth & development, Atlantic Ocean, Bacterial Toxins genetics, Bacterial Toxins immunology, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Escherichia coli drug effects, Escherichia coli growth & development, Glycolipids analysis, Glycolipids toxicity, Molecular Sequence Data, Nodularia classification, Nodularia isolation & purification, Phylogeny, RNA, Ribosomal, 16S genetics, Salmonella typhimurium drug effects, Salmonella typhimurium growth & development, Sequence Analysis, DNA, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Bacterial Toxins analysis, Geologic Sediments microbiology, Nodularia cytology, Nodularia genetics
- Abstract
A polyphasic study of a benthic Nodularia isolate (LEGE06071) from an Atlantic environment, specifically salt pans, was performed. LEGE06071 resembled both type strains of Nodularia sphaerocarpa and Nodularia harveyana, while ACOI00729 (purchased isolate) was identified as N. sphaerocarpa. The length and width of vegetative cells varied from 3.10 to 3.15 microm and from 3.71 to 4.25 microm, respectively, while heterocyts were 3.91-4.89 microm long and 4.20-4.74 microm wide. None of the isolates had aerotopes. The sequencing of the 16S rRNA gene from the two Nodularia isolates indicated that they belonged neither to Nodularia spumigena nor N. harveyana. Nodularin and other cyanotoxin synthesis-associated genes could not be detected, nor could nodularin production be detected by ELISA. However, MALDI-TOF analysis of LEGE06071 revealed the presence of other compounds, namely, glycolipids. Hence, toxicological screenings against Artemia nauplii, Escherichia coli and Salmonella typhimurium were performed. Toxic effects could only be observed against Artemia, with 48 h-LC(50) values for the aqueous and crude extract of methanol of 53.21 mg ml(-1) and 17.81 mg ml(-1), respectively. This study presents the first evidence of a non-nodularin-producing Nodularia isolate in Atlantic salt pan ecosystems and its potential ecotoxicity against Artemia sp., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)
- Published
- 2010
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