Ashmika Singh, Shristi Misser, Mushal Allam, Wai-Yin Chan, Arshad Ismail, Givemore Munhenga, Shüné V Oliver
{"title":"The Effect of Larval Exposure to Heavy Metals on the Gut Microbiota Composition of Adult <i>Anopheles arabiensis</i> (Diptera: Culicidae).","authors":"Ashmika Singh, Shristi Misser, Mushal Allam, Wai-Yin Chan, Arshad Ismail, Givemore Munhenga, Shüné V Oliver","doi":"10.3390/tropicalmed9100249","DOIUrl":null,"url":null,"abstract":"<p><p><i>Anopheles arabiensis</i> is a highly adaptable member of the <i>An</i>. <i>gambiae</i> complex. Its flexible resting behaviour and diverse feeding habits make conventional vector control methods less effective in controlling this species. Another emerging challenge is its adaptation to breeding in polluted water, which impacts various life history traits relevant to epidemiology. The gut microbiota of mosquitoes play a crucial role in their life history, and the larval environment significantly influences the composition of this bacterial community. Consequently, adaptation to polluted breeding sites may alter the gut microbiota of adult mosquitoes. This study aimed to examine how larval exposure to metal pollution affects the gut microbial dynamics of <i>An. arabiensis</i> adults. Larvae of <i>An. arabiensis</i> were exposed to either cadmium chloride or copper nitrate, with larvae reared in untreated water serving as a control. Two laboratory strains (SENN: insecticide unselected, SENN-DDT: insecticide selected) and F<sub>1</sub> larvae sourced from KwaZulu-Natal, South Africa, were exposed. The gut microbiota of the adults were sequenced using the Illumina Next Generation Sequencing platform and compared. Larval metal exposure affected alpha diversity, with a more marked difference in beta diversity. There was evidence of core microbiota shared between the untreated and metal-treated groups. Bacterial genera associated with metal tolerance were more prevalent in the metal-treated groups. Although larval metal exposure led to an increase in pesticide-degrading bacterial genera in the laboratory strains, this effect was not observed in the F<sub>1</sub> population. In the F<sub>1</sub> population, <i>Plasmodium</i>-protective bacterial genera were more abundant in the untreated group compared to the metal-treated group. This study therefore highlights the importance of considering the larval environment when searching for local bacterial symbionts for paratransgenesis interventions.</p>","PeriodicalId":23330,"journal":{"name":"Tropical Medicine and Infectious Disease","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11510740/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Tropical Medicine and Infectious Disease","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.3390/tropicalmed9100249","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
Anopheles arabiensis is a highly adaptable member of the An. gambiae complex. Its flexible resting behaviour and diverse feeding habits make conventional vector control methods less effective in controlling this species. Another emerging challenge is its adaptation to breeding in polluted water, which impacts various life history traits relevant to epidemiology. The gut microbiota of mosquitoes play a crucial role in their life history, and the larval environment significantly influences the composition of this bacterial community. Consequently, adaptation to polluted breeding sites may alter the gut microbiota of adult mosquitoes. This study aimed to examine how larval exposure to metal pollution affects the gut microbial dynamics of An. arabiensis adults. Larvae of An. arabiensis were exposed to either cadmium chloride or copper nitrate, with larvae reared in untreated water serving as a control. Two laboratory strains (SENN: insecticide unselected, SENN-DDT: insecticide selected) and F1 larvae sourced from KwaZulu-Natal, South Africa, were exposed. The gut microbiota of the adults were sequenced using the Illumina Next Generation Sequencing platform and compared. Larval metal exposure affected alpha diversity, with a more marked difference in beta diversity. There was evidence of core microbiota shared between the untreated and metal-treated groups. Bacterial genera associated with metal tolerance were more prevalent in the metal-treated groups. Although larval metal exposure led to an increase in pesticide-degrading bacterial genera in the laboratory strains, this effect was not observed in the F1 population. In the F1 population, Plasmodium-protective bacterial genera were more abundant in the untreated group compared to the metal-treated group. This study therefore highlights the importance of considering the larval environment when searching for local bacterial symbionts for paratransgenesis interventions.
阿拉伯按蚊是冈比亚按蚊复合体中适应性很强的一个成员。其灵活的休息行为和多样的进食习惯使传统的病媒控制方法无法有效控制该物种。另一个新出现的挑战是它对在污染水中繁殖的适应性,这影响了与流行病学相关的各种生活史特征。蚊子的肠道微生物群在其生活史中起着至关重要的作用,而幼虫环境会极大地影响这种细菌群落的组成。因此,适应污染的繁殖地可能会改变成蚊的肠道微生物群。本研究旨在探讨幼虫暴露于金属污染如何影响阿拉伯疟蚊成虫的肠道微生物动态。将阿拉伯疟蚊幼虫暴露于氯化镉或硝酸铜中,并以在未经处理的水中饲养的幼虫作为对照。两个实验室菌株(SENN:未选择杀虫剂;SENN-DDT:选择杀虫剂)和来自南非夸祖鲁-纳塔尔省的 F1 幼虫也受到了影响。利用 Illumina 下一代测序平台对成虫的肠道微生物群进行了测序和比较。幼虫的金属暴露影响了α多样性,而β多样性的差异更为明显。有证据表明,未处理组和金属处理组共享核心微生物群。与金属耐受性相关的细菌属在金属处理组中更为普遍。虽然幼虫接触金属会导致实验室菌株中农药降解细菌属的增加,但在 F1 群体中却没有观察到这种影响。在 F1 群体中,与金属处理组相比,未处理组中的疟原虫保护性细菌属更多。因此,这项研究强调了在寻找本地细菌共生体用于副基因干预时考虑幼虫环境的重要性。