Affiliation:
1. Centre for Limnology, NIOO-KNAW, 3631 AC Nieuwersluis
2. Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1018 WS Amsterdam, The Netherlands
3. Federal Environmental Agency, 14195 Berlin, Germany
Abstract
ABSTRACT
Assessing
and predicting bloom dynamics and toxin production by
Microcystis
requires analysis of toxic and nontoxic
Microcystis
genotypes in natural communities. We show that
genetic differentiation of
Microcystis
colonies based on rRNA
internal transcribed spacer (ITS) sequences provides an adequate basis
for recognition of microcystin producers. Consequently, ecological
studies of toxic and nontoxic cyanobacteria are now possible through
studies of rRNA ITS genotypic diversity in isolated cultures or
colonies and in natural communities. A total of 107
Microcystis
colonies were isolated from 15 lakes in Europe and
Morocco, the presence of microcystins in each colony was examined by
matrix-assisted laser desorption ionization-time of flight mass
spectrometry (MALDI-TOF MS), and they were grouped by rRNA ITS
denaturing gradient gel electrophoresis (DGGE) typing. Based on DGGE
analysis of amplified ITSa and ITSc fragments, yielding supplementary
resolution (I. Janse et al., Appl. Environ. Microbiol.
69:
6634-6643, 2003), the colonies could be differentiated into
59 classes. Microcystin-producing and non-microcystin-producing
colonies ended up in different classes. Sequences from the rRNA ITS of
representative strains were congruent with the classification based on
DGGE and confirmed the recognition of microcystin producers on the
basis of rRNA ITS. The rRNA ITS sequences also confirmed
inconsistencies reported for
Microcystis
identification based
on morphology. There was no indication for geographical restriction of
strains, since identical sequences originated from geographically
distant lakes. About 28% of the analyzed colonies gave rise to
multiple bands in DGGE profiles, indicating either aggregation of
different colonies, or the occurrence of sequence differences between
multiple operons. Cyanobacterial community profiles from two Dutch
lakes from which colonies had been isolated showed different relative
abundances of genotypes between bloom stages and between the water
column and surface scum. Although not all bands in the community
profiles could be matched with isolated colonies, the profiles suggest
a dominance of nontoxic colonies, mainly later in the season and in
scums.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference30 articles.
1. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs
2. Bolch, C. J. S., S. I. Blackburn, G. J. Jones, P. T. Orr, and P. M. Grewe. 1997 . Plasmid content and distribution in the cyanobacterial genus Microcystis Kützing ex Lemmermann (cyanobacteria: Chroococcales). Phycologia36:6-11.
3. Chorus I. and J. Bartram. 1999. Toxic cyanobacteria in
water. E. & F. N. Spon London United
Kingdom.
4. Chorus, I., V. Niesel, J. Fastner, C. Wiedner, B. Nixdorf, and K.-E. Linden-Schmidt. 2001. Environmental factors and microcystin levels in water bodies, p.159 -177. In I. Chorus (ed.),Cyanotoxins: occurrences, causes, consequences . Springer-Verlag KG, Berlin, Germany.
5. Dittmann, E., B. A. Neilan, M. Erhard, H. von Döhren, and T. Börner. 1997. Insertional mutagenesis of a peptide synthetase gene that is responsible for hepatotoxin production in the cyanobacterium Microcystis aeruginosa PCC 7806.Mol. Microbiol.26:779-787.
Cited by
110 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献