Haldar Shyamalina, Nazareth Sarita W
Department of Microbiology, Goa University, Taleigao Plateau, Taleigão, Goa 403206 India.
3 Biotech. 2018 Oct;8(10):436. doi: 10.1007/s13205-018-1441-6. Epub 2018 Oct 3.
The present study compared the taxonomic diversity and evaluated the functional attributes of the bacterial species from Mandovi and Zuari mangrove sediments, Goa, using paired-end amplicon sequencing of 16S rDNA and culture-based analyses, respectively. 16S rDNA sequencing revealed , and as the dominant phyla in both the sediments. However, the abundance of these phyla significantly differed between the samples. from Mandovi sediment, and and from Zuari sediment were the other exclusive major phyla. i, , and were the minor phyla observed in both. However, a significant difference in the distribution of minor phyla and lower bacterial taxa under each phylum was noted between the sediments, indicating that the resident microbial flora completely differed between them. This was further validated by high values from distance matrix analyses between the samples. In addition, the pathogenic sp. was recorded exclusively in Mandovi sediment, while higher abundance of ecologically important bacterial classes including , and was observed in Zuari sediment. Taken together, the data indicated that Zuari sediment was taxonomically richer than Mandovi sediment, while a greater incidence of anthropogenic activities occurred in the latter. This observation was further validated by non-parametric richness estimators which were found to be higher for Zuari sediment. The cultured bacterial isolates, all identified as , were tested for activities related to biofertilization and production of enzymes to be used for bioremediation and chemotherapeutic applications. Higher number of bacterial isolates from Mandovi was found to produce indole-acetic-acid, tannase, xylanase, and glutaminase enzymes, and could solubilize phosphate. In contrast, higher proportion of bacterial isolates from Zuari sediment were capable of producing amylase, cellulase, gelatinase, laccase, lipase, protease, and asparaginase enzymes, emphasizing the fact that the Zuari mangrove sediment is a rich reservoir for economically and biotechnologically important bacterial species.
本研究分别采用16S rDNA双端扩增子测序和基于培养的分析方法，比较了果阿邦曼多维河和祖阿里河红树林沉积物中细菌物种的分类多样性，并评估了其功能属性。16S rDNA测序显示，这两种沉积物中的优势菌门均为[具体菌门1]、[具体菌门2]和[具体菌门3]。然而，这些菌门在两个样本中的丰度存在显著差异。曼多维河沉积物中的[具体菌门4]，以及祖阿里河沉积物中的[具体菌门5]和[具体菌门6]是其他独有的主要菌门。[具体菌门7]、[具体菌门8]和[具体菌门9]是在两者中均观察到的次要菌门。然而，两种沉积物中次要菌门的分布以及每个菌门内较低级别的细菌分类群存在显著差异，这表明它们的常驻微生物群落完全不同。样本间距离矩阵分析的高值进一步验证了这一点。此外，致病性[具体菌种]仅在曼多维河沉积物中被记录到，而在祖阿里河沉积物中观察到包括[具体细菌类别1]、[具体细菌类别2]和[具体细菌类别3]在内的具有重要生态意义的细菌类别的丰度更高。综上所述，数据表明祖阿里河沉积物在分类学上比曼多维河沉积物更丰富，而后者发生人为活动的频率更高。非参数丰富度估计器进一步验证了这一观察结果，发现祖阿里河沉积物的估计值更高。所有培养的细菌分离株均鉴定为[具体菌种]，对其与生物肥料相关的活性以及用于生物修复和化疗应用的酶的产生进行了测试。发现来自曼多维河的细菌分离株产生吲哚 - 乙酸、鞣酸酶、木聚糖酶和谷氨酰胺酶的数量更多，并且能够溶解磷酸盐。相比之下，来自祖阿里河沉积物的细菌分离株中能够产生淀粉酶、纤维素酶、明胶酶、漆酶、脂肪酶、蛋白酶和天冬酰胺酶的比例更高，这强调了祖阿里河红树林沉积物是经济和生物技术重要细菌物种的丰富储存库这一事实。
