Bathyal Microaerophiles: Life Positions and Adaptations of the Santa Barbara Basin Benthos

深海微需氧微生物：圣巴巴拉盆地底栖生物的生活位置和适应

• 批准号: 9711812
• 负责人: Joan Bernhard
• 金额: $ 28万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-11-01 至 2001-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9711812&HistoricalAwards=false
• 关键词: Bathyal; Microaerophiles; Life; Positions; Adaptations

Despite the fact that mats of the filamentous sulfide oxidizing bacteria Beggiatoa are quite extensive below the neritic zone, very little is known about the eukaryotic organisms inhabiting these mats. Specimen loss and destruction of spatial information are significant obstacles to past approaches used to study these fragile sedimentary communities. To overcome these limitations, a new sampling technique was developed in which sediment cores are incubated with a fluorogenic probe to label the contained biota, and then chemically fixed, dehydrated, and embedded with low viscosity epoxy resin. Combined with novel thick sectioning methods, confocal microscopy, and state of the art digital image processing, this fluorescently labeled embedded core (FLEC) technique has provided unparalleled views of the fine scale structure of the Beggiatoa mat community in the Santa Barbara Basin (SBB). Based on initial studies using the FLEC method, it is hypothesized that Beggiatoa structures the chemical microenvironment to allow microaerophiles to live in close proximity to anaerobes and aerobes (i.e., these mats might be considered analogous to bacterial biofilms in this respect). To advance this hypothesis, the major objective of this study is to correlate meiofaunal life positions and their physiological adaptations with finescale chemical and spatial information. Furthermore, the initial FLEC studies of SBB Beggiatoa mats yielded two undescribed species or higher taxa, as well as three new and unexpected bacterial eukaryote symbioses, suggesting that the Santa Barbara Basin provides habitat for yet more undescribed species or symbioses. It is hypothesized that meiofauna possessing chemoautotrophs inhabit zones below the Beggiatoa mat, meiofauna possessing metabolic adaptations or heterotrophic symbionts co exist with the Beggiatoa, and meiofauna without special adaptations inhabit space available above the Beggiatoa mat.

尽管事实上，垫的丝状硫化物氧化细菌Beggiatoa是相当广泛的浅海区以下，很少有人知道真核生物栖息在这些垫。标本的丢失和空间信息的破坏是过去用于研究这些脆弱的沉积群落的方法的重大障碍。为了克服这些局限性，开发了一种新的采样技术，其中沉积物芯与荧光探针一起孵育，以标记所包含的生物群，然后进行化学固定，脱水，并嵌入低粘度环氧树脂。结合新的厚切片方法，共聚焦显微镜，和最先进的数字图像处理，这种荧光标记的嵌入式核心（FLEC）技术提供了无与伦比的意见，在圣巴巴拉盆地（SBB）的Beggiatoa垫社区的精细尺度结构。 基于使用FLEC方法的初步研究，假设贝贾托菌构造化学微环境以允许微需氧菌生活在厌氧菌和需氧菌附近（即，在这方面，这些垫可以被认为类似于细菌生物膜）。为了推进这一假设，本研究的主要目标是将小型底栖动物的生活位置和它们的生理适应与精细尺度的化学和空间信息相关联。此外，SBB Beggiatoa垫的初步FLEC研究产生了两个未描述的物种或更高的类群，以及三个新的和意想不到的细菌真核生物共生体，这表明圣巴巴拉盆地提供了更多的未描述的物种或共生体的栖息地。据推测，小型底栖动物具有化能自养生物栖息在贝贾托垫以下的区域，小型底栖动物具有代谢适应或异养共生体与贝贾托垫共存，小型底栖动物没有特殊的适应栖息在贝贾托垫以上的空间。