Champion A B, Rabinowitz J C
J Bacteriol. 1977 Dec;132(3):1003-20. doi: 10.1128/jb.132.3.1003-1020.1977.
Six strains of Clostridium acidiurici and three strains of C. cylindrosporum were isolated from soil samples by enrichment culture with uric acid as the source of carbon, nitrogen, and energy. The newly isolated strains were characterized by their spore morphology and the amounts of glycine and formate formed by the fermentation of uric acid. The strains were easily identified as belonging to one species or the other on the basis of spore morphology and formate production. The crystal properties and spectra of the native ferredoxins of all the strains isolated and the amino acid composition and partial carboxy-terminal sequence of all their apoferredoxins were determined. All the ferredoxins were tested for cross-reactivity with antiserum to C. acidiurici ferredoxin by microcomplement fixation. Five of the six C. acidiurici strains, which had ferredoxins with amino acid compositions identical to that from C. acidiurici, also showed immunological identity (immunological distance = 0.0). These results suggest sequence identity. The one strain with a different amino acid composition failed to show complete cross-reactivity. Two of the three C. cylindrosporum strains have ferredoxin amino acid compositions identical to that from C. cylindrosporum. The third strain had a minimum of five differences in sequence. All C. cylindrosporum strains had ferredoxins that differed considerably from C. acidiurici strains (minimum of eight to nine differences), and none of these ferredoxins cross-reacted with antisera to C. acidiurici ferredoxin. Antisera were prepared to formyltetrahydrofolate synthetase from C. acidiurici and C. cylindrosporum, and all possible comparisons were made by using immunodiffusion and microcomplement fixation. There is more intraspecies variation in the synthetases than in the ferredoxins; however, the results suggest considerable interspecies differences in both proteins. These results suggest a low degree of genomic relatedness between the two species, which contrasts sharply with their apparent high degree of phenotypic similarity.
以尿酸作为碳源、氮源和能源，通过富集培养从土壤样品中分离出6株尿酸梭菌和3株柱状芽孢梭菌。通过孢子形态以及尿酸发酵产生的甘氨酸和甲酸的量对新分离的菌株进行了表征。基于孢子形态和甲酸产生情况，这些菌株很容易被鉴定为属于这两个物种中的一个。测定了所有分离菌株的天然铁氧化还原蛋白的晶体特性和光谱，以及它们所有脱辅基铁氧化还原蛋白的氨基酸组成和部分羧基末端序列。通过微量补体结合试验，检测了所有铁氧化还原蛋白与尿酸梭菌铁氧化还原蛋白抗血清的交叉反应性。6株尿酸梭菌中的5株，其铁氧化还原蛋白的氨基酸组成与尿酸梭菌的相同，也显示出免疫同一性（免疫距离 = 0.0）。这些结果表明序列相同。氨基酸组成不同的那株菌株未显示出完全交叉反应性。3株柱状芽孢梭菌中的2株，其铁氧化还原蛋白的氨基酸组成与柱状芽孢梭菌的相同。第三株菌株在序列上至少有5个差异。所有柱状芽孢梭菌菌株的铁氧化还原蛋白与尿酸梭菌菌株的有很大差异（至少有8到9个差异），并且这些铁氧化还原蛋白都不与尿酸梭菌铁氧化还原蛋白抗血清发生交叉反应。制备了针对尿酸梭菌和柱状芽孢梭菌的甲酰四氢叶酸合成酶的抗血清，并通过免疫扩散和微量补体结合试验进行了所有可能的比较。合成酶中的种内变异比铁氧化还原蛋白中的更多；然而，结果表明这两种蛋白质在种间存在相当大的差异。这些结果表明这两个物种之间的基因组相关性程度较低，这与其明显的高度表型相似性形成鲜明对比。
