背景:红树林沉积物微生物由于其表现出多种生物修复活动的能力而越来越受到科学关注,包括广泛的环境污染物。
方法:从AlRayyisWhiteHead收集的五个AvicenniaMarina红树林沉积物样品的微生物群落,红海(KSA),使用Illumina扩增子测序16SrRNA基因进行表征。
结果:我们的研究调查了来自红海的五个红树林沉积物中有机卤化物生物修复的微生物组成和潜力。虽然变形杆菌主导了四个微生物组,拟杆菌占第五种。考虑到围绕有机卤化物的环境问题,它们的生物修复至关重要。令人鼓舞的是,我们在所有样本中发现了不同的有机卤化物呼吸细菌(OHRB),包括脱卤,除气球菌,厌氧细菌,Desulfuromonas,Geobacter,Desulfomonile,Desulfovibrio,希瓦氏杆菌和脱硫杆菌。已知这些细菌能够通过还原性脱卤作用使有机卤化物脱氯。PICRUSt分析进一步支持了这种潜力,预测有机卤化物呼吸(OHR)功能生物标志物的存在,包括大多数沉积物中针对四氯乙烯(PCE)和3-氯-4-羟基苯乙酸的还原性脱卤酶。富集文化研究证实了这一预测,通过常驻微生物群落证明PCE脱氯。PICRUSt还揭示了厌氧代谢过程的优势,表明微生物组适应沉积物的氧限制环境。
结论:这项研究为来自红海的五个红树林沉积物的细菌群落组成提供了见解。值得注意的是,在所有样本中检测到不同的OHRB,具有通过还原性脱卤途径进行有机卤化物生物修复的代谢潜力。此外,PICRUSt分析预测大多数沉积物中存在OHR的功能生物标志物,暗示封闭的微生物群落潜在的内在OHR活性。
BACKGROUND: Mangrove sediment microbes are increasingly attracting scientific attention due to their demonstrated capacity for diverse bioremediation activities, encompassing a wide range of environmental contaminants.
METHODS: The microbial communities of five Avicennia marina mangrove sediment samples collected from Al Rayyis White Head, Red Sea (KSA), were characterized using Illumina amplicon sequencing of the 16S rRNA genes.
RESULTS: Our study investigated the microbial composition and potential for organohalide bioremediation in five mangrove sediments from the Red Sea. While Proteobacteria dominated four microbiomes, Bacteroidetes dominated the fifth. Given the environmental concerns surrounding organohalides, their bioremediation is crucial. Encouragingly, we identified phylogenetically diverse organohalide-respiring bacteria (OHRB) across all samples, including Dehalogenimonas, Dehalococcoides, Anaeromyxobacter, Desulfuromonas, Geobacter, Desulfomonile, Desulfovibrio, Shewanella and Desulfitobacterium. These bacteria are known for their ability to dechlorinate organohalides through reductive dehalogenation. PICRUSt analysis further supported this potential, predicting the presence of functional biomarkers for organohalide respiration (OHR), including reductive dehalogenases targeting tetrachloroethene (PCE) and 3-chloro-4-hydroxyphenylacetate in most sediments. Enrichment cultures studies confirmed this prediction, demonstrating PCE dechlorination by the resident microbial community. PICRUSt also revealed a dominance of anaerobic metabolic processes, suggesting the microbiome\'s adaptation to the oxygen-limited environment of the sediments.
CONCLUSIONS: This study provided insights into the bacterial community composition of five mangrove sediments from the Red Sea. Notably, diverse OHRB were detected across all samples, which possess the metabolic potential for organohalide bioremediation through reductive dehalogenation pathways. Furthermore, PICRUSt analysis predicted the presence of functional biomarkers for OHR in most sediments, suggesting potential intrinsic OHR activity by the enclosed microbial community.