Characterization of a Methanogenic Community within an Algal Fed Anaerobic Digester

Table 2

Comparison of mcrA metagenomic library sequences from sludge community DNA to analogous NCBI nucleotide sequence database records through BLASTn utilizing the nonredundant database and excluding uncultured/environmental sample sequences. Only hits with an E-value < 1e ⁻⁶ were used in the final analysis. Metabolism: (1) acetoclastic, (2) CO₂ reduction with H₂ (hydrogenotrophic) and formate, and (3) methylotrophic pathways [13].

Hits	Organism	Order	Metabolism
946	Methanosaeta concilii GP-6 (CP002565.1)	Methanosarcinales	1
262	No significant similarity found	NA	NA
140	Methanosaeta concilii VeAc9 (AF313803.1)	Methanosarcinales	1
84	Methanobacterium kanagiense 169 (AB551869.1)	Methanobacteriales	2
73	Methanobacterium formicicum DSM 1535 (EF465108.1)	Methanobacteriales	2^*
55	Methanospirillum hungatei JF-1 (CP000254.1)	Methanomicrobiales	2^*
51	Methanobacterium formicicum NBRC 100475 (AB542750.1)	Methanobacteriales	2^*
48	Methanosaeta harundinacea 8Ac (AY970348.1)	Methanosarcinales	1
44	Methanolinea sp. TNR (AB496719.1)	Methanomicrobiales	2^*
43	Methanosarcina mazei strain MT (AY260440.1)	Methanosarcinales	1, 2, 3
35	Methanobacterium subterraneum NBRC 105231 (AB542754.1)	Methanobacteriales	2
22	Methanoregula formicicum SMSP (AB479391.1)	Methanomicrobiales	2^*
12	Methanoculleus palmolei (AB300784.1)	Methanomicrobiales	2^*, 3
12	Methanosarcina sp. HB-1 (AB288266.1)	Methanosarcinales	1, 2
8	Methanobacterium ivanovii NBRC 104952 (AB542751.1)	Methanobacteriales	2
6	Methanobacterium formicicum S1 mrtA (EF465103.1)	Methanobacteriales	2^*
6	Methanogenium organophilum (AB353222.1)	Methanomicrobiales	2^*
5	Methanoculleus thermophilus (AB300783.1)	Methanomicrobiales	2^*
5	Methanosarcina thermophila (AB353225.1)	Methanosarcinales	1, 2
5	Methanobacterium uliginosum DSM 2956 mrtA (EF465105.1)	Methanobacteriales	2
4	Methanosarcina mazei (EF452663.1)	Methanosarcinales	1, 2, 3
3	Methanobacterium ferruginis (AB542745.1)	Methanobacteriales	2
3	Methanobacterium petrolearium (AB542744.1)	Methanobacteriales	2
3	Methanoculleus marisnigri JR1 (CP000562.1)	Methanomicrobiales	2^*
3	Methanolinea tarda (AB300466.1)	Methanomicrobiales	2^*
3	Methanosarcina mazei LYC (AB300782.1)	Methanosarcinales	1, 2, 3
3	Methanosarcina sp. T36 (AB288292.1)	Methanosarcinales	1, 2, 3
2	Methanobacterium sp. GH (HM802935.1)	Methanobacteriales	2
2	Methanosaeta concilii DSM 3671 (AF313802.1)	Methanosarcinales	1
2	Methanosaeta thermophila PT (CP000477.1)	Methanosarcinales	1
2	Methanospirillum lacunae (AB517988.1)	Methanomicrobiales	2^*
1	Methanobacterium palustre NBRC 105230 (AB542753.1)	Methanobacteriales	2^*
1	Methanoculleus chikugoensis (AB288270.1)	Methanomicrobiales	2^*, 3
1	Methanosaeta harundinacea (HQ188223.1)	Methanosarcinales	1
1	Methanothermobacter thermautotrophicus (AE000666.1)	Methanobacteriales	2^*

2^*: organisms capable of utilizing both H₂ and formate as the electron donors for methanogenesis from CO₂. Methanogens that only use H₂/CO₂ (hydrogenotrophic) are denoted with a 2.