title: Synchrotron radiation based STXM analysis and micro-XRF mapping of differential expression of extracellular thiol groups by Acidithiobacillus ferrooxidans grown on Fe(2+) and S(0).
abstract: The differential expression of extracellular thiol groups by Acidithiobacillus ferrooxidans grown on substrates Fe(2+) and S(0) was investigated by using synchrotron radiation based scanning transmission X-ray microscopy (STXM) imaging and microbeam X-ray fluorescence (μ-XRF) mapping. The extracellular thiol groups (SH) were first alkylated by iodoacetic acid forming Protein-SCH2COOH and then the P-SCH2COOH was marked by calcium ions forming P-SCH2COOCa. The STXM imaging and μ-XRF mapping of SH were based on analysis of SCH2COO-bonded Ca(2+). The results indicated that the thiol group content of A. ferrooxidans grown on S(0) is 3.88 times to that on Fe(2+). Combined with selective labeling of SH by Ca(2+), the STXM imaging and μ-XRF mapping provided an in situ and rapid analysis of differential expression of extracellular thiol groups.
authors.affiliation: School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China. jlxia@csu.edu.cn
authors.forename: Jin-Lan
authors.initials: JL
authors.lastname: Xia
authors.forename: Hong-Chang
authors.initials: HC
authors.lastname: Liu
authors.forename: Zhen-Yuan
authors.initials: ZY
authors.lastname: Nie
authors.forename: An-An
authors.initials: AA
authors.lastname: Peng
authors.forename: Xiang-Jun
authors.initials: XJ
authors.lastname: Zhen
authors.forename: Yun
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiu-Li
authors.initials: XL
authors.lastname: Zhang
mesh_terms: D042763:Acidithiobacillus / Q000737:chemistry* / Q000378:metabolism; D005110:Extracellular Space / Q000737:chemistry*; D007501:Iron / Q000378:metabolism*; D017348:Microscopy, Electron, Scanning Transmission / Q000379:methods; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D013438:Sulfhydryl Compounds / Q000032:analysis* / Q000737:chemistry; D013455:Sulfur / Q000378:metabolism*; D017356:Synchrotrons; D014965:X-Rays
chemical_list: D013438:Sulfhydryl Compounds; D013455:Sulfur; D007501:Iron
keywords: Acidithiobacillus ferrooxidans; Extracellular thiol group; Micro-XRF mapping; STXM imaging; Synchrotron radiation