Encarnación Sergio, Guzmán Yudith, Dunn Michael F, Hernández Magdalena, del Carmen Vargas Maria, Mora Jaime
Programa de Ingeniería Metabólica, Centro de Investigación sobre Fijación de Nitrógeno, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México.
Proteomics. 2003 Jun;3(6):1077-85. doi: 10.1002/pmic.200300427.
Rhizobium etli undergoes a transition from an aerobic to a fermentative metabolism during successive subcultures in minimal medium. This metabolic transition does not occur in cells subcultured in rich medium, or in minimal medium containing either biotin or thiamine. In this report, we characterize the aerobic and fermentative metabolism of R. etli using proteome analysis. According to their synthesis patterns in response to aerobic (rich medium, minimal medium with biotin or minimal medium with thiamine) or fermentative (minimal medium without supplements) growth conditions, proteins were assigned to five different classes: (i) proteins produced only in aerobic conditions (e.g., catalase-peroxidase KatG and the E2 component of pyruvate dehydrogenase); (ii) protein produced under both conditions but strongly induced in aerobic metabolism (e.g., malate dehydrogenase and the succinyl-CoA synthetase beta subunit); (iii) proteins that were induced equally under all conditions tested (e.g., AniA, DnaK, and GroEL); (iv) proteins downregulated during aerobic metabolism, and (v) proteins specific to only one of the conditions analyzed. Northern blotting studies of katG expression confirmed the proteome data for this protein. The negative regulation of carbon metabolism proteins observed in fermentative metabolism is consistent with the drastic physiological changes which occur during this process.
在基本培养基中连续传代培养期间，费氏中华根瘤菌经历了从有氧代谢到发酵代谢的转变。这种代谢转变在丰富培养基中传代培养的细胞中不会发生，在含有生物素或硫胺素的基本培养基中传代培养的细胞中也不会发生。在本报告中，我们使用蛋白质组分析来表征费氏中华根瘤菌的有氧代谢和发酵代谢。根据蛋白质在有氧（丰富培养基、含生物素的基本培养基或含硫胺素的基本培养基）或发酵（无补充剂的基本培养基）生长条件下的合成模式，将蛋白质分为五类：（i）仅在有氧条件下产生的蛋白质（例如，过氧化氢酶-过氧化物酶KatG和丙酮酸脱氢酶的E2组分）；（ii）在两种条件下都产生但在有氧代谢中强烈诱导的蛋白质（例如，苹果酸脱氢酶和琥珀酰辅酶A合成酶β亚基）；（iii）在所有测试条件下均被同等诱导的蛋白质（例如，AniA、DnaK和GroEL）；（iv）在有氧代谢过程中下调的蛋白质，以及（v）仅在所分析的一种条件下特异的蛋白质。katG表达的Northern印迹研究证实了该蛋白质的蛋白质组数据。在发酵代谢中观察到的碳代谢蛋白的负调控与该过程中发生的剧烈生理变化一致。
