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Characterization of microbial community structure during continuous anaerobic digestion of straw and cow manure.

Sun L, Pope PB, Eijsink VG, Schnürer A - Microb Biotechnol (2015)

Bottom Line: Compared with manure itself, digestion of manure resulted in a higher abundance of an uncultured class WWE1 and lower abundance of Bacilli.Adding straw to the digesters increased the level of Bacteroidia, while increasing the operating temperature decreased the level of this class and instead increased the relative abundance of an uncultured genus affiliated to order MBA08 (Clostridia).A considerable fraction of bacterial sequences could not be allocated to genus level, indicating that novel phylotypes are resident in these communities.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, SE-750 07, Uppsala, Sweden.

No MeSH data available.


Relative abundance of archaea 16S rRNA gene at the genus level in manure (S1 and S2 correspond to duplicate samples) and in laboratory-scale digesters processing: (1) manure as sole substrate (RM); (2) stream-exploded straw and manure, operating constantly at 37°C (RTcSS); and (3) steam-exploded straw and manure, operating temperatures 37°C, 44°C and 52°C (R37SS, R44SS and R52SS), where R1 and R2 represent parallel digesters.
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fig02: Relative abundance of archaea 16S rRNA gene at the genus level in manure (S1 and S2 correspond to duplicate samples) and in laboratory-scale digesters processing: (1) manure as sole substrate (RM); (2) stream-exploded straw and manure, operating constantly at 37°C (RTcSS); and (3) steam-exploded straw and manure, operating temperatures 37°C, 44°C and 52°C (R37SS, R44SS and R52SS), where R1 and R2 represent parallel digesters.

Mentions: For archaea, the OTU table was randomly subsampled 640 times prior to downstream analysis. It was possible to assign more than 99.6% of the sequences at the phylum level, among which more than 98.1% belonged to the phylum Euryarchaeota (mainly the classes Methanomicrobia and Methanobacteria). The rest of the sequences (< 1.9%) were represented by Crenarchaeota and unclassified sequences. For each sample, at least 95.1% of the sequences could be assigned to genus level (Fig. 2). Methanosarcina from the order Methanosarcinales, known to utilize both acetate and hydrogen, was the most dominant genus in digesters RM (97.4–99.5%), RTcSS and R37SS (90.3–98.8%), R44SS (96.9–97.7%), and R52SS (74.1–77.1%), while this genus represented only 1.3% and 6.4% of the reads from the two manure samples. Sequences belonging to the acetoclastic methanogen, Methanosaeta, were only detected in two samples and at a low level, in RM on day 42 (1.1%) and in RTcSS R1 on day 9 (0.2%). For hydrogenotrophic methanogens, the genus Methanoculleus represented less than 0.3% in all digesters operating at 37°C and 44°C, but corresponded to 6.9–11.9% in R52SS. In the manure samples, the genus Methanoculleus represented less than 0.4% of the community; instead, the archaeal community was dominated by Methanobrevibacter from the order Methanobacteriales (85.2% and 93.3%). However, the levels of Methanobrevibacter were low in all digesters (< 3.1%). In addition, sequences related to the genus Methanobacterium were found at low levels in the low-medium temperature digesters (37–44°C) and in the manure (< 2.5%), but were more abundant at the higher digestion temperature (12.3–14.4% in R52SS).


Characterization of microbial community structure during continuous anaerobic digestion of straw and cow manure.

Sun L, Pope PB, Eijsink VG, Schnürer A - Microb Biotechnol (2015)

Relative abundance of archaea 16S rRNA gene at the genus level in manure (S1 and S2 correspond to duplicate samples) and in laboratory-scale digesters processing: (1) manure as sole substrate (RM); (2) stream-exploded straw and manure, operating constantly at 37°C (RTcSS); and (3) steam-exploded straw and manure, operating temperatures 37°C, 44°C and 52°C (R37SS, R44SS and R52SS), where R1 and R2 represent parallel digesters.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4554469&req=5

fig02: Relative abundance of archaea 16S rRNA gene at the genus level in manure (S1 and S2 correspond to duplicate samples) and in laboratory-scale digesters processing: (1) manure as sole substrate (RM); (2) stream-exploded straw and manure, operating constantly at 37°C (RTcSS); and (3) steam-exploded straw and manure, operating temperatures 37°C, 44°C and 52°C (R37SS, R44SS and R52SS), where R1 and R2 represent parallel digesters.
Mentions: For archaea, the OTU table was randomly subsampled 640 times prior to downstream analysis. It was possible to assign more than 99.6% of the sequences at the phylum level, among which more than 98.1% belonged to the phylum Euryarchaeota (mainly the classes Methanomicrobia and Methanobacteria). The rest of the sequences (< 1.9%) were represented by Crenarchaeota and unclassified sequences. For each sample, at least 95.1% of the sequences could be assigned to genus level (Fig. 2). Methanosarcina from the order Methanosarcinales, known to utilize both acetate and hydrogen, was the most dominant genus in digesters RM (97.4–99.5%), RTcSS and R37SS (90.3–98.8%), R44SS (96.9–97.7%), and R52SS (74.1–77.1%), while this genus represented only 1.3% and 6.4% of the reads from the two manure samples. Sequences belonging to the acetoclastic methanogen, Methanosaeta, were only detected in two samples and at a low level, in RM on day 42 (1.1%) and in RTcSS R1 on day 9 (0.2%). For hydrogenotrophic methanogens, the genus Methanoculleus represented less than 0.3% in all digesters operating at 37°C and 44°C, but corresponded to 6.9–11.9% in R52SS. In the manure samples, the genus Methanoculleus represented less than 0.4% of the community; instead, the archaeal community was dominated by Methanobrevibacter from the order Methanobacteriales (85.2% and 93.3%). However, the levels of Methanobrevibacter were low in all digesters (< 3.1%). In addition, sequences related to the genus Methanobacterium were found at low levels in the low-medium temperature digesters (37–44°C) and in the manure (< 2.5%), but were more abundant at the higher digestion temperature (12.3–14.4% in R52SS).

Bottom Line: Compared with manure itself, digestion of manure resulted in a higher abundance of an uncultured class WWE1 and lower abundance of Bacilli.Adding straw to the digesters increased the level of Bacteroidia, while increasing the operating temperature decreased the level of this class and instead increased the relative abundance of an uncultured genus affiliated to order MBA08 (Clostridia).A considerable fraction of bacterial sequences could not be allocated to genus level, indicating that novel phylotypes are resident in these communities.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, SE-750 07, Uppsala, Sweden.

No MeSH data available.