Department of Botany and Microbiology and OU Biocorrosion Center, University of Oklahoma, Norman, OK, USA.
Environ Microbiol. 2012 Jul;14(7):1762-71. doi: 10.1111/j.1462-2920.2012.02721.x. Epub 2012 Mar 19.
Two thermophilic archaea, strain PK and strain MG, were isolated from a culture enriched at 80°C from the inner surface material of a hot oil pipeline. Strain PK could ferment complex organic nitrogen sources (e.g. yeast extract, peptone, tryptone) and was able to reduce elemental sulfur (S°), Fe(3+) and Mn(4+) . Phylogenetic analysis revealed that the organism belonged to the order Thermococcales. Incubations of this strain with elemental iron (Fe°) resulted in the abiotic formation of ferrous iron and the accumulation of volatile fatty acids during yeast extract fermentation. The other isolate, strain MG, was a H(2) :CO(2) -utilizing methanogen, phylogenetically affiliated with the genus Methanothermobacter family. Co-cultures of the strains grew as aggregates that produced CH(4) without exogenous H(2) amendment. The co-culture produced the same suite but greater concentrations of fatty acids from yeast extract than did strain PK alone. Thus, the physiological characteristics of organisms both alone and in combination could conceivably contribute to pipeline corrosion. The Thermococcus strain PK could reduce elemental sulfur to sulfide, produce fatty acids and reduce ferric iron. The hydrogenotrophic methanogen strain MG enhanced fatty acid production by fermentative organisms but could not couple the dissolution Fe° with the consumption of water-derived H(2) like other methanogens.
两株嗜热古菌，菌株 PK 和菌株 MG，是从 80°C 热输油管道内表面材料的富集培养物中分离得到的。菌株 PK 可以发酵复杂的有机氮源（如酵母提取物、蛋白胨、胰蛋白胨），并能够还原元素硫（S°）、Fe(3+) 和 Mn(4+)。系统发育分析表明，该生物属于热球菌目。该菌株与元素铁（Fe°）孵育导致亚铁的非生物形成，并在酵母提取物发酵过程中积累挥发性脂肪酸。另一个分离株，菌株 MG，是一种 H(2)：CO(2)利用的产甲烷菌，与 Methanothermobacter 科的属密切相关。两株菌的共培养物以聚集体的形式生长，在没有外加 H(2)的情况下产生 CH(4)。与单独的菌株 PK 相比，共培养物从酵母提取物中产生了相同的脂肪酸，但浓度更高。因此，这些生物单独和组合的生理特性可能会导致管道腐蚀。Thermococcus 菌株 PK 可以将元素硫还原为硫化物、产生脂肪酸并还原三价铁。氢营养型产甲烷菌菌株 MG 可以通过发酵生物来提高脂肪酸的产量，但不能像其他产甲烷菌那样将溶解的 Fe°与水衍生的 H(2)的消耗相耦合。
