Transcriptional Response of the Sulfur Chemolithoautotroph Thiomicrospira crunogena to Dissolved Inorganic Carbon Limitation

Author:

Dobrinski Kimberly P.1,Enkemann Steven A.2,Yoder Sean J.2,Haller Edward1,Scott Kathleen M.1

Affiliation:

1. Department of Integrative Biology, University of South Florida, Tampa, Florida, USA

2. Microarray Core Laboratory, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Tampa, Florida, USA

Abstract

ABSTRACT The hydrothermal vent gammaproteobacterium Thiomicrospira crunogena inhabits an unstable environment and must endure dramatic changes in habitat chemistry. This sulfur chemolithoautotroph responds to changes in dissolved inorganic carbon (DIC) (DIC = CO 2 + HCO 3 + CO 3 −2 ) availability with a carbon-concentrating mechanism (CCM) in which whole-cell affinity for DIC, as well as the intracellular DIC concentration, increases substantially under DIC limitation. To determine whether this CCM is regulated at the level of transcription, we resuspended cells that were cultivated under high-DIC conditions in chemostats in growth medium with low concentrations of DIC and tracked CCM development in the presence and absence of the RNA polymerase inhibitor rifampin. Induction of the CCM, as measured by silicone oil centrifugation, was hindered in the presence of rifampin. Similar results were observed for carboxysome gene transcription and assembly, as assayed by quantitative reverse transcription-PCR (qRT-PCR) and transmission electron microscopy, respectively. Genome-wide transcription patterns for cells grown under DIC limitation and those grown under ammonia limitation were assayed via microarrays and compared. In addition to carboxysome genes, two novel genes ( Tcr_1019 and Tcr_1315 ) present in other organisms, including chemolithoautotrophs, but whose function(s) has not been elucidated in any organism were found to be upregulated under low-DIC conditions. Likewise, under ammonia limitation, in addition to the expected enhancement of ammonia transporter and P II gene transcription, the transcription of two novel genes ( Tcr_0466 and Tcr_2018 ) was measurably enhanced. Upregulation of all four genes ( Tcr_1019 , 4-fold; Tcr_131 , ∼7-fold; Tcr_0466 , >200-fold; Tcr_2018 , 7-fold), which suggests that novel components are part of the response to nutrient limitation by this organism, was verified via qRT-PCR.

Publisher

American Society for Microbiology

Subject

Molecular Biology,Microbiology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3