Maresca Diamante, De Filippis Francesca, Robertiello Alessandro, Mauriello Gianluigi
Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, NA, Italy.
Microorganisms. 2019 Jul 15;7(7):200. doi: 10.3390/microorganisms7070200.
Phenotypic and genotypic evidence indicates that many LAB strains can grow in presence of oxygen and can shift from fermentative to aerobic and/or respiratory metabolism. The aerobic and respiratory growth of several LAB species have been studied, allowing the selection of strains showing improved biomass production, long-term survival, and resistance under oxygen and stress conditions. The aim of this work was to observe the adaptation of two strains, described in a previous work, to aerobic (air injection) and respiratory (air injection plus hemin and menaquionone) conditions obtained in a batch bioreactor. One strain showed the higher biomass production and oxygen consumption as well as the lower acidification in respiratory condition. Instead, the other one grew better in aerobic condition, even though the higher resistance to cold-starvation stress was registered in respiratory condition. In silico analysis revealed notable differences between AL3 and AL5 genomes and that of the type strain. This work contributes to understanding the adaptation response of lactobacilli to aerobic and respiratory metabolism. We demonstrated that the supposed activation of respiratory metabolism may provide several modifications to cell physiology. These features may be relevant in some technological and health-promoting applications, including starter and probiotic formulations.
表型和基因型证据表明，许多乳酸菌菌株能够在有氧环境下生长，并且能够从发酵代谢转变为有氧和/或呼吸代谢。已经对几种乳酸菌的有氧和呼吸生长进行了研究，从而能够筛选出在氧气和应激条件下表现出更高生物量产量、长期存活率和抗性的菌株。这项工作的目的是观察在之前的一项研究中描述的两株菌株，对在分批式生物反应器中获得的有氧（注入空气）和呼吸（注入空气加血红素和甲萘醌）条件的适应性。其中一株菌株在呼吸条件下表现出更高的生物量产量和氧气消耗以及更低的酸化程度。相反，另一株菌株在有氧条件下生长得更好，尽管在呼吸条件下对冷饥饿应激的抗性更高。计算机分析揭示了AL3和AL5基因组与模式菌株基因组之间的显著差异。这项工作有助于理解乳酸菌对有氧和呼吸代谢的适应性反应。我们证明，假定的呼吸代谢激活可能会给细胞生理学带来一些改变。这些特性在一些技术和促进健康的应用中可能具有相关性，包括发酵剂和益生菌制剂。
