Comparative 16S rRNA gene surveys of granular sludge from three upflow anaerobic bioreactors treating purified terephthalic acid (PTA) wastewater

2011 ◽  
Vol 64 (7) ◽  
pp. 1406-1412 ◽  
Author(s):  
S. D. Perkins ◽  
N. B. Scalfone ◽  
L. T. Angenent

The microbial communities from three upflow anaerobic bioreactors treating purified terephthalic acid (PTA) wastewater were characterized with 16S ribosomal RNA gene sequencing surveys. Universal bacterial and archaeal primers were used to compare the bioreactor communities to each other. A total of 1,733 bacterial sequences and 383 archaeal sequences were characterized. The high number of Syntrophus spp. and Pelotomaculum spp. found within these reactors indicates efficient removal of benzoate and terephthalate. Under anaerobic conditions benzoate can be degraded through syntrophic associations between these bacteria and hydrogen-scavenging microbes, such as Desulfovibrio spp. and hydrogenotrophic methanogens, which remove H2 to force the thermodynamically unfavourable reactions to take place. The authors did not observe a relatively high percentage of hydrogenotrophic methanogens with the archaeal gene survey because of a high acetate flux (acetate is a main component in PTA wastewater and is the main degradation product of terephthalate/benzoate fermentation), and because of the presence of Desulfovibrio spp. (a sulfate reducer that scavenges hydrogen). The high acetate flux also explains the high percentage of acetoclastic methanogens from the genus Methanosaeta among the archaeal sequences. A group of uncultured bacteria (OD1) may be involved in the degradation of p-toluate (4-methyl benzoate), which is a component of PTA wastewater.

Author(s):  
E. Fernández-Palacios ◽  
Xudong Zhou ◽  
Mabel Mora ◽  
David Gabriel

In this study, the long-term performance and microbial dynamics of an Upflow Anaerobic Sludge Blanket (UASB) reactor targeting sulfate reduction in a SOx emissions treatment system were assessed using crude glycerol as organic carbon source and electron donor under constant S and C loading rates. The reactor was inoculated with granular sludge obtained from a pulp and paper industry and fed at a constant inlet sulfate concentration of 250 mg S-SO42−L−1 and a constant C/S ratio of 1.5 ± 0.3 g Cg−1 S for over 500 days. Apart from the regular analysis of chemical species, Illumina analyses of the 16S rRNA gene were used to study the dynamics of the bacterial community along with the whole operation. The reactor was sampled along the operation to monitor its diversity and the changes in targeted species to gain insight into the performance of the sulfidogenic UASB. Moreover, studies on the stratification of the sludge bed were performed by sampling at different reactor heights. Shifts in the UASB performance correlated well with the main shifts in microbial communities of interest. A progressive loss of the methanogenic capacity towards a fully sulfidogenic UASB was explained by a progressive wash-out of methanogenic Archaea, which were outcompeted by sulfate-reducing bacteria. Desulfovibrio was found as the main sulfate-reducing genus in the reactor along time. A progressive reduction in the sulfidogenic capacity of the UASB was found in the long run due to the accumulation of a slime-like substance in the UASB.


2004 ◽  
Vol 70 (6) ◽  
pp. 3475-3484 ◽  
Author(s):  
Ashvini Chauhan ◽  
Andrew Ogram ◽  
K. R. Reddy

ABSTRACT Nutrient runoff from the Everglades Agricultural Area resulted in a well-documented gradient of phosphorus concentrations in soil and water, with concomitant ecosystem-level changes, in the northern Florida Everglades. It was recently reported that sulfate-reducing prokaryote assemblage composition, numbers, and activities are dependent on position along the gradient (H. Castro, K. R. Reddy, and A. Ogram, Appl. Environ. Microbiol. 68:6129-6137, 2002). The present study utilized a combination of culture- and non-culture-based approaches to study differences in composition of assemblages of syntrophic and methanogenic microbial communities in eutrophic, transition, and oligotrophic areas along the phosphorus gradient. Methanogenesis rates were much higher in eutrophic and transition regions, and sequence analysis of 16S rRNA gene clone libraries constructed from samples taken from these regions revealed differences in composition and activities of syntroph-methanogen consortia. Methanogens from eutrophic and transition regions were almost exclusively composed of hydrogenotrophic methanogens, with approximately 10,000-fold-greater most probable numbers of hydrogenotrophs than of acetotrophs. Most cultivable strains from eutrophic and transition regions clustered within novel lineages. In non-culture-based studies to enrich syntrophs, most bacterial and archaeal clones were either members of novel lineages or closely related to uncultivated environmental clones. Novel cultivable Methanosaeta sp. and fatty acid-oxidizing bacteria related to the genera Syntrophomonas and Syntrophobacter were observed in microcosms containing soil from eutrophic regions, and different lines of evidence indicated the existence of novel syntrophic association in eutrophic regions.


2020 ◽  
Vol 77 (6) ◽  
pp. 1081-1088
Author(s):  
Tayyibe Alpay ◽  
Burcin Karabey ◽  
Nuri Azbar ◽  
Guven Ozdemir

2001 ◽  
Vol 43 (1) ◽  
pp. 77-82 ◽  
Author(s):  
O.-C. Chan ◽  
W.-T. Liu ◽  
H. H. Fang

The microbial community structure of granular sludge from an upflow anaerobic sludge blanket (UASB) reactor treating brewery effluent was studied by denaturing gradient gel electrophoresis (DGGE). Twelve major bands were observed in the DGGE fingerprint for the Bacteria domain and four bands for the Archaea domain. Of the bacterial bands observed, six were successfully purified and sequenced. Among them, three were related to the gram-positive low G+C group, one to the Delta subclass of the Proteobacteria, one to the Gamma subclass, and one to the Cytophaga group with no close related sequence. The 16S rRNA sequences of the four archaeal bands were closely associated with Methanosaeta concilii and Methanobacterium formicum.


Sign in / Sign up

Export Citation Format

Share Document