Liu Sijia, Zheng Nan, Wang Jiaqi, Zhao Shengguo
College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
Front Microbiol. 2024 Apr 2;15:1376994. doi: 10.3389/fmicb.2024.1376994. eCollection 2024.
The rumen microbial community plays a crucial role in the digestion and metabolic processes of ruminants. Although sequencing-based studies have helped reveal the diversity and functions of bacteria in the rumen, their physiological and biochemical characteristics, as well as their dynamic regulation along the digestion process in the rumen, remain poorly understood. Addressing these gaps requires pure culture studies to demystify the intricate mechanisms at play. Bacteria exhibit morphological differentiation associated with different species. Based on the difference in size or shape of microorganisms, size fractionation by filters with various pore sizes can be used to separate them.
In this study, we used polyvinylidene difluoride filters with pore sizes of 300, 120, 80, 40, 20, 8, 6, 2.1, and 0.6 μm. Bacterial suspensions were successively passed through these filters for the analysis of microbial population distribution using 16S rRNA gene sequences.
We found that bacteria from the different pore sizes were clustered into four branches (> 120 μm, 40-120 μm, 6-20 μm, 20-40 μm, and < 0.6 μm), indicating that size fractionation had effects on enriching specific groups but could not effectively separate dominant groups by cell size alone. The species of unclassified Flavobacterium, unclassified Chryseobacterium, unclassified , , unclassified Caulobacteraceae, unclassified , unclassified , unclassified , unclassified , unclassified , unclassified Alphaproteobacteria, and unclassified SR1 can be efficiently enriched or separated by size fractionation.
In this study, we investigated the diversity of sorted bacteria populations in the rumen for preliminary investigations of the relationship between the size and classification of rumen bacteria that have the potential to improve our ability to isolate and culture bacteria from the rumen in the future.
瘤胃微生物群落对反刍动物的消化和代谢过程起着至关重要的作用。尽管基于测序的研究有助于揭示瘤胃中细菌的多样性和功能，但它们的生理生化特征以及在瘤胃消化过程中的动态调节仍知之甚少。解决这些差距需要进行纯培养研究，以揭开其中复杂机制的神秘面纱。细菌表现出与不同物种相关的形态分化。基于微生物大小或形状的差异，可使用具有不同孔径的过滤器进行大小分级来分离它们。
在本研究中，我们使用了孔径为300、120、80、40、20、8、6、2.1和0.6μm的聚偏二氟乙烯过滤器。细菌悬浮液依次通过这些过滤器，利用16S rRNA基因序列分析微生物种群分布。
我们发现，来自不同孔径的细菌聚为四个分支（>120μm、40 - 120μm、6 - 20μm、20 - 40μm和<0.6μm），这表明大小分级对富集特定菌群有影响，但仅靠细胞大小不能有效分离优势菌群。未分类的黄杆菌属、未分类的金黄杆菌属、未分类的、、未分类的柄杆菌科、未分类的、未分类的、未分类的、未分类的、未分类的、未分类的α-变形菌纲和未分类的SR1菌群可通过大小分级有效富集或分离。
在本研究中，我们调查了瘤胃中分类细菌种群的多样性，以便初步研究瘤胃细菌大小与分类之间的关系，这有可能提高我们未来从瘤胃中分离和培养细菌的能力。
