Liu Y, Balkwill D L, Aldrich H C, Drake G R, Boone D R
Department of Environmental Biology, Portland State University, OR 97207-0751, USA.
Int J Syst Bacteriol. 1999 Apr;49 Pt 2:545-56. doi: 10.1099/00207713-49-2-545.
A strain of anaerobic, syntrophic, propionate-oxidizing bacteria, strain LYPT (= OCM 661T; T = type strain), was isolated and proposed as representative of a new genus and new species, Smithella propionica gen. nov., sp. nov. The strain was enriched from an anaerobic digestor and isolated. Initial isolation was as a monoxenic propionate-degrading co-culture containing Methanospirillum hungateii JF-1T as an H2- and formate-using partner. Later, an axenic culture was obtained by using crotonate as the catabolic substrate. The previously described propionate-degrading syntrophs of the genus Syntrophobacter also grow in co-culture with methanogens such as Methanospirillum hungateii, forming acetate, CO2 and methane from propionate. However, Smithella propionica differs by producing less methane and more acetate; in addition, it forms small amounts of butyrate. Smithella propionica and Syntrophobacter wolinii grew within similar ranges of pH, temperature and salinity, but they differed significantly in substrate ranges and catabolic products. Unlike Syntrophobacter wolinii, Smithella propionica grew axenically on crotonate, although very slowly. Co-cultures of Smithella propionica grew on propionate, and grew slowly on crotonate or butyrate. Syntrophobacter wolinii and Syntrophobacter pfennigii grow on propionate plus sulfate, whereas Smithella propionica did not. Comparisons of 16S rDNA genes indicated that Smithella propionica is most closely related to Syntrophus, and is more distantly related to Syntrophobacter.
分离出了一株厌氧、互营、氧化丙酸盐的细菌，LYPT菌株（= OCM 661T；T = 模式菌株），并提议将其作为一个新属和新物种的代表，即丙酸史密斯氏菌属（Smithella propionica），新属，新种。该菌株从厌氧消化器中富集并分离得到。最初分离时是作为一种单菌的丙酸盐降解共培养物，其中含有亨氏甲烷螺菌（Methanospirillum hungateii）JF-1T作为利用氢气和甲酸盐的伙伴。后来，通过使用巴豆酸盐作为分解代谢底物获得了纯培养物。先前描述的互营杆菌属（Syntrophobacter）的丙酸盐降解互营菌也能与产甲烷菌如亨氏甲烷螺菌在共培养中生长，从丙酸盐形成乙酸盐、二氧化碳和甲烷。然而，丙酸史密斯氏菌的不同之处在于产生的甲烷较少而乙酸较多；此外，它还会形成少量的丁酸盐。丙酸史密斯氏菌和沃氏互营杆菌（Syntrophobacter wolinii）在相似的pH、温度和盐度范围内生长，但它们在底物范围和分解代谢产物方面有显著差异。与沃氏互营杆菌不同，丙酸史密斯氏菌能在巴豆酸盐上纯培养生长，尽管生长非常缓慢。丙酸史密斯氏菌的共培养物能在丙酸盐上生长，在巴豆酸盐或丁酸盐上生长缓慢。沃氏互营杆菌和芬氏互营杆菌（Syntrophobacter pfennigii）能在丙酸盐加硫酸盐上生长，而丙酸史密斯氏菌则不能。16S rDNA基因的比较表明，丙酸史密斯氏菌与互营杆菌属关系最为密切，与互营菌属的关系则较远。
