摘要
在青岛汇泉湾沿岸沉积物中发现了大量海洋趋磁细菌,最大丰度可达10~5个/cm^3。透射电镜观察发现该菌菌体形态多样,有球形或卵球形、长短杆状、弧状和螺旋状,其中球形或卵球形趋磁细菌占绝对优势。电镜观察还发现该菌磁小体的排列方式多样化,大多数呈链状排列,有单链、双链及多链,还有的呈环状或者成簇排列。磁小体的形态也多种多样,有正方体、棱柱体、立方八面体、子弹头状、片状和齿状。用 RFLP 方法分析了70个克隆测序,得到10条不同序列。经16S rRNA 系统发育分析,发现9个属于α-变形菌亚纲,1个属于γ-变形菌亚纲,共有8个不同的属,优势种属于未培养的海洋趋磁球菌。所有菌株与最接近的海洋趋磁球菌的相似性并不高(76.4%～89.4%),表明该海区的趋磁细菌为新发现的微生物资源。
A large number of magnetotactic bacteria were collected from the sediments of the Huiquan Bay coast near Qingdao city （China）. Their abundance reached up to 105 cells/cm^3. Their diverse morphotypes, including cocci, ovoids, rods, vibrios and spirilla were observed, and the coccoid shape was most abundant. The magnetosomes of magetotactic bacteria arranged in one, two or multiple chains. Irregular arrangement of magnetosomes was also evident. Morphology of magnetosome crystals was homogenous in a given cell, but displayed various shapes, including square, cubo-octahedron, parallelepiped, elongated hexagonal prismatic, bullet-shaped and tooth-shaped in different cells. The morphological diversity of marine magnetotactic bacteria was confirmed by RFLP and sequence analysis of 16S rRNA. At least 10 different taxo- nomic groups were identified. Among them, nine belonged to α-Proteobacteria and one exception was γ-Proteobacteria. Compared to known axenic or uncultivated magnetotactic bacteria, the 16S rRNA sequences of most magnetotactic bacteria collected from Huiquan Bay exhibited low sequence identities ranging from 76.4% to 89.4%. These results suggest a specific geo-distribution of the magnetotactic bacteria collected from the China Sea.
出处
《高技术通讯》
CAS
CSCD
北大核心
2008年第3期312-317,共6页
Chinese High Technology Letters
基金
973计划(2006CB400604)
中国科学院海外杰出学者基金(2003-1-5,2006-1-15)
人类前沿科学研究计划(HFSP,RGP0035/2004-C)项目
作者简介
女，1982年生，硕士生；研究方向：海洋微生物学。
与第一作者同等贡献，女，1976年生，博士生；研究方向：海洋生物学。
通讯作者，E-mail：txiao@MS．qdio．ac．cn
