中文摘要：

【目的】颊下囊是蚂蚁口前腔中一个特殊的袋状结构,在蚂蚁取食过程中,固体食物和其它颗粒在进入食道前被过滤在颊下囊中,稍后被蚂蚁从口前腔排出,这种过滤机制保证了主要利用液体食物的蚂蚁整个消化道的畅通。本文旨在揭示蚂蚁颊下囊结构及其内含物中存在的细菌类群及其可能在蚂蚁的消化、清洁以及其它方面发挥的潜在作用。【方法】利用扫描电镜确定了日本弓背蚁颊下囊在蚂蚁头部的位置及其形状,然后采用传统的细菌分离培养与细菌16S r RNA基因序列分析相结合的方法进行了颊下囊内含物以及蚁巢内土壤样品细菌的分离培养研究。【结果】（1）颊下囊位于蚂蚁口腔的后侧,呈袋状结构,内部含有大量的固体颗粒物质;（2）3个蚁巢工蚁颊下囊内含物每克样品中可培养细菌的菌落总数（cfu/g）数量差异较大,并且显著大于同巢土壤样品的细菌cfu/g数量;（3）从3个蚁巢的工蚁颊下囊内含物中共分离到11属的细菌,分别隶属于厚壁菌门（Firmicutes）、放线菌门（Actinobacteria）和γ-变形菌纲（γ-Proteobacteria）三大类群,其中放线菌门细菌为优势类群;在属级水平上,巢1和巢2工蚁颊下囊内含物中的优势菌群为微杆菌属,分别占47.83%和49.73%,巢3优势菌群为不动杆菌属和微杆菌属,分别占37.27%和30%;3个蚁巢土壤样品优势菌均为芽孢杆菌属,分别占各自分离总菌落数的49.69%、56.22%和44.79%。（4）蚁巢土壤中所分离出的细菌均能在同巢工蚁的颊下囊内含物中分离得到,但同一蚁巢蚂蚁颊下囊内含物与其巢内土壤的细菌组成存在明显差异;不同蚁巢蚂蚁颊下囊内含物的细菌组成也存在明显差异。【结论】蚂蚁的颊下囊中存在丰富的细菌种类,在蚁巢土壤中分离到的细菌均能在颊下囊中发现,而在颊下囊中分离到的部分细菌并没有在相应的蚁巢土壤样品中分离到。

英文摘要：

[Objectives] The infrabuccal pocket is a special pouch-like filtration device located in the preoral cavity of ants. During feeding, solid food particles and other solid materials are filtered and compacted in the infrabuccal pocket before entering the alimentary tract. Any waste is later ejected from the preoral cavity thereby helping prevent the alimentary tract from blocking. In this paper we explore the bacterial groups in the contents of the infrabuccal pocket and their potential roles in digestion, cleaning and other aspects of ant biology. [Methods] The location of the infrabuccal pocket in the head of Camponotus japonicus was identified with scanning microscopy, and the bacteria in the infrabuccal pocket investigated using a culture-dependent method and 16 S r RNA gene sequence analysis. [Results]（1） The infrabuccal pocket is a pouch-like structure located in the posterior oral cavity containing a large number of solid particles.（2） The cfu/g of bacteria in the infrabuccal pockets of ants from three colonies varied significantly, but all were greater than in their respective nest soil.（3） Eleven bacterial genera were isolated from the infrabuccal pockets of ants from three colonies. These belonged to the Firmicutes, Actinobacteria and γ-Proteobacteria respectively. Actinobacteria was the dominant bacterial group. At the generic level, Microbacterium was the most dominant bacterial group in the 1st and 2nd colonies, accounting for 47.83% and 49.73% respectively of the total. Acinetobacter and Microbacterium were the two dominant bacterial groups in the 3rd colony, accounting for 37.27% and 30% of the total, respectively. However, Bacillus was the dominant bacteria in all three nest soil samples, accounting for 49.69%、56.22% and 44.79% respectively.（4） All bacteria isolated from nest soil can be found in the infrabuccal pocket but the bacterial composition of the infrabuccal pocket and nest soil differs within the same colony. [Conclusion] The bacterial composition of the infrabuccal pock