Te Aka Mātuatua-School of Science, Te Whare Wānanga o Waikato-University of Waikato, Private Bag 3105, Hamilton 3240, Aotearoa, New Zealand.
FEMS Microbiol Lett. 2023 Jan 17;370. doi: 10.1093/femsle/fnad124.
Methylobacterium species are abundant colonizers of the phyllosphere due to the availability of methanol, a waste product of pectin metabolism during plant cell division. The phyllosphere is an extreme environment, with a landscape that is heterogeneous and continuously changing as the plant grows and is exposed to high levels of ultraviolet irradiation. Geographically, New Zealand (NZ) has been isolated for over a million years, has a biologically diverse flora, and is considered a biodiversity hotspot, with most native plants being endemic. We therefore hypothesize that the phyllosphere of NZ native plants harbor diverse groups of Methylobacterium species. Leaf imprinting using methanol-supplemented agar medium was used to isolate bacteria, and diversity was determined using ARDRA and 16S rRNA gene sequencing. Methylobacterium species were successfully isolated from the phyllosphere of 18 of the 20 native NZ plant species in this study, and six different species were identified: M. marchantiae, M. mesophilicum, M. adhaesivum, M. komagatae, M. extorquens, and M. phyllosphaerae. Other α, β, and γ-Proteobacteria, Actinomycetes, Bacteroidetes, and Firmicutes were also isolated, highlighting the presence of other potentially novel methanol utilizers within this ecosystem. This study identified that Methylobacterium are abundant members of the NZ phyllosphere, with species diversity and composition dependent on plant species.
甲基杆菌属物种是叶际的丰富定植者，因为甲醇的可用性，甲醇是植物细胞分裂过程中果胶代谢的废物产物。叶际是一个极端的环境，随着植物的生长和暴露在高水平的紫外线照射下，景观是异质的和不断变化的。从地理位置上看，新西兰（NZ）已经隔离了一百多万年，拥有丰富多样的植物群，被认为是生物多样性热点地区，大多数本地植物都是特有种。因此，我们假设 NZ 本地植物的叶际蕴藏着多种多样的甲基杆菌属物种。使用添加甲醇的琼脂培养基进行叶印，以分离细菌，并使用 ARDRA 和 16S rRNA 基因测序来确定多样性。本研究成功地从 20 种 NZ 本地植物中的 18 种中分离出叶际甲基杆菌属，鉴定出 6 种不同的物种：Methylobacterium marchantiae、Methylobacterium mesophilicum、Methylobacterium adhaesivum、Methylobacterium komagatae、Methylobacterium extorquens 和 Methylobacterium phyllosphaerae。还分离出其他α、β和γ-变形菌、放线菌、拟杆菌门和厚壁菌门，突出了该生态系统中其他潜在的新型甲醇利用者的存在。本研究表明，甲基杆菌属是 NZ 叶际的丰富成员，其物种多样性和组成取决于植物物种。
