Supplementary information:
Figure S1: Rarefaction curves indicating the observed number of operational taxonomic units (OTUs), at a genetic distance of 3% in different chironomid egg mass and larva samples.
Figure S2: UPGMA clustering of bacterial communities from chironomid egg masses and larvae. Significant differences were found between the bacterial communities associated with the egg masses and the larvae (AMOVA: F1,9 =4.3, P0.001).
Figure S3. Phylogenetic tree representing heavy metal resistant bacterial isolates from chironomid egg masses and larvae. The isolates accession numbers are indicated in parentheses after the isolates names. The sequence alignments were performed using the CLUSTAL W program and the trees were generated using the neighbor-joining method with Kimura 2 parameter distances in MEGA 4.1 software. Bootstrap values (from 1000 replicates) greater than 50% are shown at the branch points. The bar indicates a 2% sequence divergence.
Table S1: Bacterial abundances at the genus level, in chironomid egg masses and larvae. The table presents OTUs that were identified at the genus level, whose prevalence in the sequence reads were less than 1% (on average) in the egg masses and / or larvae. About 40% and 25% of all the genera that were identified from the egg mass and larval bacterial communities, respectively, may potentially have detoxifying abilities (only one reference per genus is specified). See also Table 1 for identified genera with abundances of more than 1%.
Class/Genus / Mean abundance % (prevalence) / Known detoxifying activity / ReferenceEgg masses / Larvae
Alphaproteobacteria
Phenylobacterium / 0.9 (6/6) / 0.7 (3/5) / Aminopyrine degradation / Blecher et al., 1981
Paracoccus / 0.5 (6/6) / 0.1 (4/5) / Chlorpyrifos and trichloro- pyridinoldegradation / Xu et al. 2008
Brevundimonas / 0.4 (6/6) / 0.08 (3/5) / Connected tobiostimulation of a heavily PAH-contaminated soil / Vinas et al., 2005b
Devosia / 0.3 (6/6) / 0.05 (2/5) / Decontamination of hexachlorocyclohexane / Verma et al., 2009
Rhodobacter / 0.2 (6/6) / 0.1 (3/5) / Cadmium bioremediation / Bai et al., 2008
Hyphomonas / 0.1 (4/6) / 0.003 (1/5) / Heavy metalsbioremediation / Pal et al., 2008
Betaproteobacteria
Thauera / 0.8 (6/6) / 0.2 (3/5) / Toluene degradation / Shinoda et al., 2004
Propionivibrio / 0.6 (6/6) / 0.2 (3/5) / Perchlorate reduction / Thrash et al., 2010
Zoogloea / 0.3 (6/6) / 0.1 (3/5) / Phenanthrene and pyrene degradation / Li et al., 2005a
Uruburuella / 0.3 (5/6) / 0.01 (1/5) / none
Azonexus / 0.2 (6/6) / 0.05 (2/5) / Denitrifying bacteria from sludge wastewater treatment plant / Quan et al., 2006
Simplicispira / 0.1 (4/6) / 0.01 (2/5) / Denitrifying bacteria / Wen et al., 1999
Burkholderia / 0.1 (3/6) / 0.03 (1/5) / Xenobiotic pollutants degradation / O’Sullivan and Mahenth- iralingam,
2005
Naxibacter / 0.1 (3/6) / - / Arsenic-resistant / Huang, 2010
Massilia / 0.02 (2/6) / 0.1 (2/5) / Phenanthrene degradation / Loick et al., 2011
Laribacter / 0.02 (4/6) / 0.1 (2/5) / -
Gammaproteobacteria
Rheinheimera / 0.6 (6/6) / 0.1 (3/5) / -
Tolumonas / 0.5 (6/6) / 0.1 (3/5) / Identified from a microbial consortium capable of U(VI) reduction / Akob et al., 2008
Moraxella / 0.3 (6/6) / - / Mineralization of p-nitrophenol / Errampalli et al., 1999
Steroidobacter / 0.3 (4/6) / - / Polycyclic aromatic degradation / Cebron et al., 2011
Thermomonas / 0.1 (6/6) / 0.08 (2/5) / Associated with petroleum land treatment unit / Kaplan et al., 2003
Shewanella / 0.03 (3/6) / 0.2 (3/5) / Chromium (VI) reduction / Guha et al., 2001
Deltaproteobacteria
Desulfobulbus / 0.4 (6/6) / 0.1 (4/5) / Isolated during Uranium polluted soil bioremediation / Groudev et al., 2008
Bdellovibrio / 0.3 (6/6) / 0.03 (1/5) / -
Desulfopila / 0.02 (3/6) / 0.1 (4/5) / -
Actinobacteria
Bifidobacterium / 0.5 (6/6) / 0.3 (4/5) / -
Brevibacterium / 0.1 (1/6) / 0.09 (2/5) / Zinc absorption / Taniguchi et al., 2000
Leucobacter / 0.1 (6/6) / 0.2 (3/5) / Cr (VI) reduction / Sarangi et al., 2007
Mycobacterium / 0.1 (6/6) / 0.2 (5/5) / Degradation of straight-chain aliphatic and high-molecular weight
polycyclic aromatic hydrocarbons / Bogan et al., 2003
Agrococcus / 0.1 (3/6) / 0.01 (2/5) / -
Corynebacterium / 0.04 (3/6) / 0.1 (3/5) / Bioremediation of arsenic / Mateos et al., 2006
Gordonia / 0.003 (1/6) / 0.1 (2/5) / Degradation of car engine base oil / Koma et al., 2003
Nocardioides / 0.005 (1/6) / 0.7 (2/5) / Dechlorination and mineralization of atrazine / Topp et al., 2000
Micrococcus / - / 0.2 (3/5) / Bioremediation of contaminated surface water / Li et al., 2005b
Bacteroidia
Dysgonomonas / 0.1 (6/6) / 0.8 (5/5) / -
Paludibacter / 0.1 (5/6) / - / Bacterial consortium, growth on toluene / Muller et al., 2009
Flavobacteria
Fluviicola / 0.3 (6/6) / 0.006 (1/5) / -
Fusobacteria
Sebaldella / 0.3 (6/6) / 0.04 (2/5) / -
Sphingobacteria
Haliscomenobacter / 0.2 (6/6) / 0.05 (3/5) / Associated with wastewater treatment systems / Miller et al., 2007
Caldilineae
Caldilinea / 0.05 (4/6) / 1.9 (3/5) / Bioremediation of oil waste / Maciel et al., 2009
Bacilli
Bacillus / 0.3 (5/6) / 0.1 (3/5) / Cr (VI) reduction / Liu et al., 2006
Streptococcus / 0.1 (5/6) / 0.08 (2/5) / -
Clostridia
Anaerovorax / 0.4 (6/6) / 0.2 (4/5) / Dechlorinating mixed culture / Rowe et al., 2008
Subdoligranulum / 0.4 (6/6) / 3.3 (5/5) / -
Acetobacterium / 0.1 (6/6) / 0.005 (1/5) / Degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) / Sherburne et al., 2005
Aminomonas / 0.1 (5/6) / 0.01 (2/5) / Identified in polycyclic aromatic hydrocarbon degrading microbial consortium / Vinas et al., 2005a
Faecalibacterium / 0.1 (6/6) / 0.008 (1/5) / -
Clostridium / 0.08 (5/6) / 0.1 (5/5) / Nitroaromatic contaminants bioremediation / Sembries and Crawford, 1997
Erysipelotrichia
Erysipelothrix / 0.3 (6/6) / 0.02 (1/5) / Identified in a common effluent treatment plant / Kapley et al., 2007
Bulleidia / 0.01 (1/6) / 0.2 (4/5) / -
Gemmatimonadetes
Gemmatimonas / 0.1 (5/6) / - / -
Verrucomicrobiae
Haloferula / 0.1 (3/6) / - / -
Luteolibacter / 0.02 (3/6) / 0.1 (2/5) / Favored development in PAH-contaminated soil / Cebron et al., 2009
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