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Full Length
Research Paper
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Variation of Anaeromyxobacter community structure and
abundance in paddy soil slurry over flooding time
Chao Zhu1, Shu-Hong Xia1, Bao-li Wang1
and Dong Qu2*
1College
of Life Science, Northwest A and F University, 3 Taicheng
Road, Yangling 712100, Shaanxi, China.
2College
of Resources and Environment, Northwest A and F University,
3 Taicheng Road, Yangling 712100, Shaanxi, China.
*Corresponding author.
E-mail:
dongqu@nwsuaf.edu.cn
or
304545693@qq.com.
Tel:
+86-(0)29-87082624.
Accepted 19 September, 2011 |
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Abstract |
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Cultivation-independent techniques like PCR-amplified
restriction fragment length polymorphism (PCR-RFLP)
of 16S rRNA genes and real-time PCR were applied
to assess the abundance, diversity and
phylogenetic composition of Anaeromyxobacter
communities over time in flooded, unplanted
paddy soil slurries. Six Anaeromyxobacter
communities were sampled from anoxic slurries at
1 h, and 1, 5, 10, 20 and 30 days while the Fe
(II) concentrations were measured also.
Bacterial Genomic DNA was extracted and PCR-amplified
to obtain 16S rDNA fragments of
Anaeromyxobacter which were cloned to
construct 6 16s rDNA libraries. Eventually 10
major Anaeromyxobacter types were
identified by RFLP fingerprintings. Results
showed that the optimal increasing phase of Fe
(II) was from 1h to nearly 10 days, being
correspond with the growth phase of the
abundance of Anaeromyxobacter. The
highest diversity appeared in slurry at 30 days
and the lowest was found at 30 days. Jackknife
Environment Clusters by UniFrac showed that
phylogenetic compositions of Anaeromyxobacter
communities in slurries at 10 and 20 days were
the most similar. By evolutionary distance
analysis, our 10 major Anaeromyxobacter
types were diverged into Group 1 and 2 in
phylogenetic tree, while Group 1 was the
exclusive collection of clones from our
experiment. Major type P1 was present in all
slurries abundantly and P9 only existed in
slurry at 5 days. The abundance of
Anaeromyxobacter spp., calculated as its
proportion of 16S rDNA copies to the value of
total Bacteria, was from 0.242% at 1 h to
5.135% at 10 days. We demonstrated that flooding
time led to successional dynamics of major types
and variable abundance of Anaeromyxobacter
community. Flooding time also influenced the
diversity of Anaeromyxobacter community
on some extent. Canonical correspondence
analysis (CCA) revealed that
Anaeromyxobacteria spp. abundance had
interrelation with Fe (II) content and the
influenced the distribution of the slurries in
the Biplot. Moreover, our study provides
valuable information for the further isolation
of Anaeromyxobacter strains from paddies.
Key words:
Anaeromyxobacter;
paddy soil, community structure, abundance,
PCR-RFLP, flooding time.
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