Central Sericultural Research and Training Institute, Mysuru, Karnataka, 570008, India.
Probiotics Antimicrob Proteins. 2020 Jun;12(2):635-640. doi: 10.1007/s12602-019-09580-3.
Microorganisms play an important role in the growth and development of numerous insect species. The mulberry silkworm, Bombyx mori (Lepidoptera), harbors several bacteria in its midgut aiding the metabolic processes; however, the variability of bacterial spp. present in the midgut and their role(s) in the growth and development of the silkworm are poorly understood. The present work compares the diversity of midgut bacterial communities in silkworms of variable voltinism (Pure Mysore, PM: multivoltine; CSR2: bivoltine and PM × CSR2: crossbreed) through metagenomics. The predominance of Enterococcus (30.30%) followed by Bacillus (16.96%) was observed in PM, whereas Lactobacillus (56.56%) followed by Enterococcus (10.58%) was seen only in CSR2. Interestingly, crossbreed midgut harbored diverse bacterial communities (36.21% Lactobacillus, 25.94% Bacillus, 8.1% Enterococcus, and 18.37% uncultured bacteria). Metagenomic profiles indicate variability in the gut bacterial population in different kinds of silkworms influencing the physiological activities accordingly. The dominant bacteria, particularly lactobacilli, bacilli, and enterococci could be further explored for identifying the potential probiotic consortia based on a literature survey and potential involvement in nutrient absorption, disease/stress tolerance, and improved economic traits.
微生物在许多昆虫物种的生长和发育中起着重要作用。桑蚕（鳞翅目）的中肠中栖息着几种有助于代谢过程的细菌；然而，中肠中存在的细菌 spp 的可变性及其在蚕生长和发育中的作用（多个）知之甚少。本工作通过宏基因组学比较了不同可变性（纯 Mysore，PM：多化性；CSR2：二化性和 PM×CSR2：杂交种）蚕的中肠细菌群落的多样性。在 PM 中观察到肠球菌（30.30%），其次是芽孢杆菌（16.96%）占优势，而 CSR2 中仅观察到乳杆菌（56.56%），其次是肠球菌（10.58%）。有趣的是，杂交种中肠含有多样化的细菌群落（36.21%乳杆菌、25.94%芽孢杆菌、8.1%肠球菌和 18.37%未培养细菌）。宏基因组图谱表明不同种类的蚕中肠道细菌种群的可变性相应地影响生理活动。根据文献调查和在营养吸收、疾病/压力耐受和提高经济性状方面的潜在参与，可进一步探索优势细菌，特别是乳杆菌、芽孢杆菌和肠球菌，以确定潜在的益生菌联合体。
