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Microbes have been confirmed to play key role in biogeochemistry of antimony. However, the impact of indigenous bacteria (from active mines) on the behavior of dissolved antimony remained poorly understood. In current study, the hyper antimony-resistant strain, Achromobacter sp. 25-M, isolated from the world largest antimony deposit, Xikuangshan antimony deposit, was evaluated for its role in dissolved Sb(V) and Sb(III) precipitation and removal. Despite of the high resistance to Sb(III) (up to 50 mM), the facultative alkaliphile, 25-M was not capable of Sb(III) oxidation. Meanwhile 25-M can produce high amount of exopolymeric substance (EPS) with the presence of Sb, which prompted us to investigate the potential role of EPS in the precipitation and removal of Sb. To this end, 2 mM of Sb(III) and Sb(V) were added into the experimental systems with and without 25-M to discern the interaction mechanism between microbe and antimony. After 96 hrs' incubation, 88% [1.73 mM (210 mg/L)] of dissolved Sb(V) and 80% [1.57 mM (190 mg/L)] of dissolved Sb(III) were removed. X-ray diffraction and energy dispersive spectroscopy analysis confirmed the formation of valentinite (Sb 2 O 3) in Sb(III) amended system and a solitary Sb(V) mineral mopungite [NaSb(OH) 6 ] in Sb(V) amended group with microbes. Conversely, no precipitate was detected in abiotic systems. Morphologically valentinite was bowtie and mopungite was pseudo-cubic as indicated by scanning electronic microscopy. EPS was subjected to fourier transform infrared (FT-IR) analysis. FT-IR analysis suggested that –OH and –COO groups were responsible for the complexation and ligand exchange with Sb(III) and Sb(V), respectively. Additionally, the C–H group and N–H group could be involved in π-π interaction and chelation with Sb species. All these interactions between Sb and functional groups in EPS may subsequently favore the formation of valentinite and mopungite. Collectively, current results suggested that EPS play fundamental role in bioprecipitation of Sb, which offered a new strategy in Sb bioremediation. [Display omitted] • Achromobacter sp. 25-M isolated from Sb rock of XKS mine showed strong resistance of antimony up to 50 mM. • 25-M can remove 80% of Sb(III) and 88% of Sb(V) via bioprecipitation as valentinite and mopungite, respectively. • EPS produced by 25-M may play the fundamental role in bioprecipitation of antimony. • -OH, –COO, C–H, N–H groups of EPS may facilitate complexation, ligand exchange, π-π interaction and chelation with Sb. [ABSTRACT FROM AUTHOR]

• TBM patients had higher expression of death and suppression of survival biomarkers. • Caspase-3 positively correlated with TNFα, IL6 and MDA. • Caspase-3 negatively correlated with XIAP, GSH and catalase. • Caspase-3 expression was higher in patients with definite TBM. • Patients who died had higher expression of caspase-3 and suppression of XIAP. The balancing factor of apoptosis, survival, inflammatory and oxidative stress biomarkers may determine the clinico-radiological severity and death in the patients with tuberculous meningitis (TBM). We report the relationship of death [caspase-3, malondialdehyde (MDA), tumor necrosis factor-α (TNFα), interleukin 6 (IL6)] and survival biomarkers [X-linked inhibitory apoptotic protein (XIAP), IL10, glutathione (GSH) and catalase] in TBM, and its role in determining disease severity and death. The diagnosis of TBM was based on clinical, MRI and cerebrospinal fluid (CSF) findings. Their clinical and MRI findings were noted. The severity of TBM was categorized as stages I to III. Serum and CSF caspase-3 and XIAP were measured by ELISA, and TNFα, IL6 and IL10 gene expression in peripheral blood mononuclear cells using RT-PCR (reverse-transcriptase polymerase chain reaction). Plasma MDA, GSH and catalase were measured by spectrophotometer. There were 40 patients with TBM whose mean age was 31.6 years and 50% were females. TBM patients had higher expression of death (caspase-3, TNFα, IL6, and MDA) and suppression of survival biomarkers (XIAP, catalase and GSH) compared to the healthy controls. Caspase-3 positively correlated with TNFα, IL6 and MDA, and negatively with XIAP, GSH and catalase. Patients with longer duration of illness and definite TBM had higher expression of caspase-3. Patients who died has higher expression of caspase-3 and suppression of XIAP compared to those who survived. It can be concluded from this study that there is up-regulation of death signals and suppression of survival signals in TBM. [ABSTRACT FROM AUTHOR]