Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands.
Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands; Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium.
Sci Total Environ. 2022 Jul 10;829:154472. doi: 10.1016/j.scitotenv.2022.154472. Epub 2022 Mar 8.
Sulfated glycosaminoglycans (sGAG) are negatively charged extracellular polymeric substances that occur in biofilms from various environments. Yet, it remains unclear whether these polymers are acquired from the external environment or produced by microbes in the biofilm. To resolve this, we analyzed the presence of sGAGs in samples of an acidophilic biofilm collected from Sulfur Cave in Puturosu Mountain (Romania), an environment that is largely inaccessible to contamination. A maximum of 55.16 ± 2.06 μg sGAG-like polymers were recovered per mg of EPS. Enzymatic treatment with chondroitinase ABC resulted in a decrease of the mass of these polymers, suggesting the structure of the recovered sGAG is similar to chondroitin. Subsequent FT-IR analysis of these polymers revealed absorbance bands at 1230 cm, 1167 cm and 900 cm, indicating a possible presence of polysaccharides and sulfate. Analysis of genomic sequences closely related to those predominant in the acidophilic biofilm, contained genes coding for sulfotransferase (an enzyme needed for the production of sGAG), which supports the hypothesis of microbial synthesis of sGAGs within the biofilm.
硫酸化糖胺聚糖 (sGAG) 是带负电荷的细胞外聚合物质，存在于各种环境中的生物膜中。然而，目前尚不清楚这些聚合物是从外部环境中获得的，还是生物膜中的微生物产生的。为了解决这个问题，我们分析了从罗马尼亚普图罗苏山硫磺洞采集的嗜酸生物膜样本中 sGAG 的存在情况，该环境基本上不可能受到污染。每毫克 EPS 最多可回收 55.16 ± 2.06 μg sGAG 样聚合物。用软骨素酶 ABC 进行酶处理会导致这些聚合物质量下降，表明回收的 sGAG 的结构与软骨素相似。对这些聚合物进行随后的傅里叶变换红外 (FT-IR) 分析显示在 1230 cm、1167 cm 和 900 cm 处有吸收带，表明可能存在多糖和硫酸盐。对与嗜酸生物膜中主要存在的序列密切相关的基因组序列进行分析，包含编码硫酸转移酶（产生 sGAG 所需的酶）的基因，这支持了生物膜中微生物合成 sGAG 的假设。
