Heilongjiang Provincial Key Laboratory of Environmental Microbiology and Recycling of Argo-Waste in Cold Region, College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, 163319, People's Republic of China.
Engineering Research Center of Processing and Utilization of Grain By-Products, Ministry of Education, Daqing, 163319, People's Republic of China.
World J Microbiol Biotechnol. 2022 Mar 19;38(5):76. doi: 10.1007/s11274-022-03262-z.
Magnetotactic bacteria (MTB) distribute widely in sediment habitats and play critical roles in iron cycling. Here, the vertical distribution of morphology and phylogenetic diversity of MTB in sediments (0-15 cm) of three lakes (open waterbody, Bailonghu, BL; semi-enclosed waterbody, Yaoquanhu, YQ; enclosed waterbody, Yueyapao, YY) in Wudalianchi volcanic field (China) were investigated. TEM showed the appearance of coccoid, rod-shaped, oval-shaped, and arc-shaped MTB. With the increase of BL sediment depth, the number of rod-shaped and spherical MTB decreased and increased, respectively. High-throughput sequencing indicated that Alphaproteobacterial MTB dominantly thrived in these lakes regardless of waterbody types. In BL and YY, the dominant genus was Magnetospirillum (44.99-70.80%) which showed a peak in the middle layer. In YQ, the genus Magnetospira was dominant in the upper (52.36%) and middle (66.56%) layer and Magnetococcus (69.63%) existed dominantly in the bottom layer. The vertical distribution of MTB in sediments of these lakes decreased first and then increased. Functional analysis showed that ABC transporter and two-component system of MTB changed significantly with the sediment depth. RDA indicated that the distribution of Magnetospirillum was positively associated with sulfide, pH, and TC. These findings will expand our knowledge of the vertical distribution of MTB in volcanic lakes.
磁性细菌（MTB）广泛分布于沉积物生境中，在铁循环中起着关键作用。本研究调查了中国五大连池火山区三个湖泊（开阔水体白龙湖，BL；半封闭水体药泉湖，YQ；封闭水体月牙泡，YY）沉积物（0-15 cm）中 MTB 的形态和系统发育多样性的垂直分布。TEM 显示了 MTB 呈球形、杆状、椭圆形和弧形。随着 BL 沉积物深度的增加，杆状和球形 MTB 的数量分别减少和增加。高通量测序表明，无论水体类型如何，变形菌门的 MTB 都在这些湖泊中占主导地位。在 BL 和 YY 中，优势属为磁螺旋菌属（44.99-70.80%），在中层达到峰值。在 YQ 中，上（52.36%）中和中（66.56%）层的优势属为磁螺菌属，底层的优势属为磁球菌属（69.63%）。这些湖泊沉积物中 MTB 的垂直分布先减少后增加。功能分析表明，MTB 的 ABC 转运蛋白和双组分系统随沉积物深度的变化而显著变化。RDA 表明，磁螺旋菌的分布与硫化物、pH 值和 TC 呈正相关。这些发现将扩大我们对火山湖中 MTB 垂直分布的认识。
