细菌是雪莲菌中的重要功能菌群，对于雪莲菌的形成及其功能作用的发挥有着重要作用，因而探明其细菌的种群特征具有重大意义。本文采用聚合酶链式反应-变性梯度凝胶电泳（PCR-DGGE）和16S rDNA测序技术对3个西藏雪莲菌颗粒（A、B和C）中细菌多样性进行了研究。DGGE电泳结果显示，样品的丰度值介于12~16之间，细菌多样性指数在1.79~2.11之间，相似性指数在0.62~0.77之间。通过对DGGE指纹图谱优势条带切胶测序结果显示：它们分别属于马乳酒样乳杆菌（Lactobacillus kefiranofaciens）、乳球菌属（Lactococcus）、乳杆菌属（Lactobacillus）、嗜热链球菌（Streptococcus thermophilus）、开菲尔乳杆菌（Lactobacillus kefir）、气单胞菌属（Aeromonas）和醋酸菌属（Acetobacter）。旨在为雪莲菌微生物资源开发以及加快雪莲菌工业化生产奠定基础。

Bacteria are important functional microorganisms in Tibetan kefir grains, and play an important role in their formation and functions. Therefore, exploring the bacterial species in Tibetan kefir grains is of great significance. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rDNA sequencing were used to study the bacterial diversity of three Tibetan kefir grains (A, B, and C) from different places. The DGGE results showed that the richness indices in Tibetan kefir grains were between 12 and 16, the diversity indices of all samples were between 1.79 and 2.11, and the similarity indices were between 0.62 and 0.77. The PCR-DGGE dominant bands were cut and sequenced, and the results indicated that the dominant bacteria belonged to Lactobacillus kefiranofaciens, Lactococcus spp., Lactobacillus spp., Streptococcus thermophilus, Lactobacillus kefir, Aeromonas spp., and Acetobacter spp. This work provides a theoretical basis for the development of microbial resources and the acceleration of the industrial production of Tibetan kefir grains.

国家863计划项目（2013AA102106）