Interspecies electron transfer (IET) occurs in many microbial communities, enabling extracellular electron exchange for syntrophic utilization of mixed resources. Various mechanisms of IET have been characterized including direct IET (DIET) and hydrogen IET (HIT) but their evolution throughout syntrophic adaptation has not been investigated through an omics approach. A syntrophic coculture of Geobacter sulfurreducens and Pseudomonas aeruginosa was established and evolved in restricted medium. The medium required cooperative metabolism due to preferential utilization of formate and fumarate by P. aeruginosa and G. sulfurreducens respectively. Pure cultures did not yield significant growth while substantial growth was observed in cocultures. The syntrophy was not reliant on phenazine, since Δphz mutant strain cocultures grew, however appeared to rely on cytochromes as evidenced from the stunted growth G. sulfurreducens ΔomcZ and ΔomcS mutant cocultures. SWATH (sequential window acquisition of all theoretical spectra) MS (mass spectrometry) proteomic analysis of initial cocultures revealed upregulation in DIET-associated cytochromes, whereas adapted cocultures revealed upregulation in HybA, a G. sulfurreducens uptake hydrogenase critical to HIT. This suggests DIET plays a critical role in the establishment of syntrophy between G. sulfurreducens and P. aeruginosa but is later consolidated with HIT as the cocultures adapt. This is the first instance to show a temporal distribution of DIET and HIT within the same coculture.

种间电子转移（IET）发生在许多微生物群落中，能够进行胞外电子交换，以合成营养的方式利用混合资源。IET的各种机制已被表征，包括直接IET（DIET）和氢IET（HIT），但尚未通过组学方法研究它们在整个营养养分适应中的进化。建立了减少土壤杆菌和铜绿假单胞菌的营养共培养，并在限制性培养基中进化。由于P优先利用甲酸和富马酸，该培养基需要协同代谢。铜绿假单胞菌和G ^。还原硫分别。纯培养物没有产生明显的生长，而在共培养物中观察到了显着的生长。由于Δphz突变菌株共培养，该同养型不依赖于吩嗪，但是从生长受阻的生长G可以看出，它似乎依赖于细胞色素。硫还原Δ omcZ和Δ OMCS突变体共培养物中。初始共培养物的SWATH（所有理论光谱的顺序窗口采集）MS（质谱）蛋白质组学分析显示，与DIET相关的细胞色素表达上调，而适应性共培养物显示HybA（G）中的表达上调。还原硫摄取对HIT至关重要的氢化酶。这表明DIET在建立G之间的同质性中起着至关重要的作用。硫还原和P。铜绿假单胞菌，但后来随着共培养的适应而与HIT合并。这是首次显示同一共培养物中DIET和HIT的时间分布。