中文摘要：

为了进一步完善嗜酸性氧化亚铁硫杆菌（简称A．f菌）的硫氧化途径，实验研究了A．f菌对单质硫的氧化行为，分析了L-半胱氨酸对单质硫生物氧化的影响，通过接触角测定、Zeta电位测定与硫的K边x-射线近边结构光谱分析（XANES）等方法研究了A．f菌作用前后单质硫表面性质的变化．结果表明：A．f菌以单质硫为能源时，其生长延滞期约为100h，培养240h达到最大细菌浓度（约为6．0×10^8个／mL）；A．f菌作用后，单质硫由疏水性变为亲水性，等电点由2．5增大到3．0，在硫样品表面发现了链状硫与含巯基的有机物质的存在；在培养基中添加0．5g·L-1的L-半胱氨酸能够促进单质硫的生物氧化，XANES结果表明生物作用后的硫样品表面链状硫与巯基物相对含量均有所提高，分别从39．2％和15．4％增大到48．5％和27．7％．

英文摘要：

In order to improve the pathway of the sulphur bio - oxidation mediated by Acidithiobacillus ferrooxidans （ short for A. f）, the oxidation behaviors of elemental sulphur mediated by A. f were ex- perimented, and the influence of L - Cysteine addition into the mediums was discussed for the elemen- tal sulphur bio - oxidation. The surface characteristics of sulphur before and after bio - oxidation were analyzed through the methods of contact angle, Zeta potential and sulfur K -edge X -ray absorption near edge structure spectrometry （ short for XANES）. The results indicated that with the elemental sul- phur as energy resource, A. fexperienced the lag phase of about 100 hours and reached the maximum bacterial concentration of 6.0 × 10^8cells/mL after 240 hours; after A. f oxidation, the surface charac- teristics of elemental sulphur changed from hydrophobicity to hydrophilicity, and the isoelectric point changed from 2.5 to 3.0 ; meanwhile, the intermediate products of linear sulphur and organisms with sulfhydryl group were observed on the surface of sulphur samples oxidized by A. f; the addition of L - Cysteine with 0.5 g .L -1 into the culture media accelerated the elemental sulphur oxidation obviously, which was testified through the ganisms with sulphydryl group increased amounts of linear sulphur （from 15.4% to 27.7% ） measured （from 39.2% to 48.5% ） and or- by XANES.