Rojas Connie A, Marks Stanley L, Borras Eva, Lesea Hira, McCartney Mitchell M, Coil David, Davis Cristina E, Eisen Jonathan A
University of California - Davis.
Res Sq. 2023 May 9:rs.3.rs-2883555. doi: 10.21203/rs.3.rs-2883555/v1.
Animals rely on volatile chemical compounds for their communication and behavior. Many of these compounds are sequestered in endocrine and exocrine glands and are synthesized by anaerobic microbes. While the volatile organic compound (VOC) or microbiome composition of glandular secretions has been investigated in several mammalian species, few have linked specific bacterial taxa to the production of volatiles or to specific microbial gene pathways. Here, we use metagenomic sequencing, mass-spectrometry based metabolomics, and culturing to profile the microbial and volatile chemical constituents of anal gland secretions in twenty-three domestic cats (), in attempts to identify organisms potentially involved in host odor production. We found that the anal gland microbiome was dominated by bacteria in the genera , and , and showed striking variation among individual cats. Microbiome profiles also varied with host age and obesity. Metabolites such as fatty-acids, ketones, aldehydes and alcohols were detected in glandular secretions. Overall, microbiome and metabolome profiles were modestly correlated (r=0.17), indicating that a relationship exists between the bacteria in the gland and the metabolites produced in the gland. Functional analyses revealed the presence of genes predicted to code for enzymes involved in VOC metabolism such as dehydrogenases, reductases, and decarboxylases. From metagenomic data, we generated 85 high-quality metagenome assembled genomes (MAGs). Of these, four were inferred to have high relative abundance in metagenome profiles and had close relatives that were recovered as cultured isolates. These four MAGs were classified as , and . They represent strong candidates for further investigation of the mechanisms of volatile synthesis and scent production in the mammalian anal gland.
动物依靠挥发性化合物进行交流和行为。其中许多化合物被隔离在内分泌腺和外分泌腺中，由厌氧微生物合成。虽然已经在几种哺乳动物物种中研究了腺分泌物的挥发性有机化合物（VOC）或微生物群组成，但很少有人将特定的细菌类群与挥发性物质的产生或特定的微生物基因途径联系起来。在这里，我们使用宏基因组测序、基于质谱的代谢组学和培养方法来分析23只家猫肛门腺分泌物的微生物和挥发性化学成分，试图识别可能参与宿主气味产生的生物体。我们发现，肛门腺微生物群以、和属的细菌为主，并且在个体猫之间表现出显著差异。微生物群谱也随宿主年龄和肥胖程度而变化。在腺分泌物中检测到脂肪酸、酮、醛和醇等代谢物。总体而言，微生物群和代谢组谱之间存在适度的相关性（r = 0.17），表明腺体中的细菌与腺体中产生的代谢物之间存在关系。功能分析揭示了预测编码参与VOC代谢的酶（如脱氢酶、还原酶和脱羧酶）的基因的存在。从宏基因组数据中，我们生成了85个高质量的宏基因组组装基因组（MAG）。其中，有四个在宏基因组谱中推断具有较高的相对丰度，并且有密切的亲缘关系，这些亲缘关系被作为培养分离株回收。这四个MAG被分类为、和。它们是进一步研究哺乳动物肛门腺挥发性合成和气味产生机制的有力候选对象。
