Zeng, G. | Search bioRxiv

bioRxiv2018

A novel function of Galactomyces candidum in highly efficient ammonia nitrogen removal from low C:N wastewater

A strain of bacteria that demonstrated efficient nitrogen removal potential under low C:N conditions was screened from landfill leachate. The strain was identified as Galactomyces candidum by ITS sequencing, and growth density and removal of ammonia nitrogen were assessed after 24 h of incubation. The results showed that the optimum ammonia nitrogen reduction conditions for G. candidum was at pH 8.0 and 30 {degrees}C, with a C:N ratio of 1.5:1; the highest rate of ammonia nitrogen removal was 93.1%. This novel function of G. candidum offers great potential in the removal of ammonia nitrogen from sewage, especially in low C:N wastewater. Our study provides a new theoretical basis for the industrial application of bacteria in the biochemical treatment of wastewater and reduces environmental pollution.\n\nA novel function and potential of Galamyces candidum in the removal of ammonia nitrogen from wastewater treatment was found, which provides a theoretical basis for the treatment of ammonia in wastewater.

microbiology↗

bioRxiv2017

High-throughput fitness profiling of Zika virus E protein reveals different roles for N-linked glycosylation during infection of mammalian and mosquito cells

Zika virus (ZIKV) infection causes Guillain-Barre syndrome and severe birth defects. ZIKV envelope (E) protein is the major viral protein involved in cell receptor binding and entry and therefore considered one of the major determinants in ZIKV pathogenesis. Here, we report a gene-wide mapping of functional residues of ZIKV E protein using a mutant library with changes covering every nucleotide position. By comparing the replication fitness of every viral mutant between mosquito and human cells, we identified that mutations affecting N-linked glycosylation at N154 position display the most divergence. Through characterizing individual mutants, we show that, while ablation of N-linked glycosylation selectively benefits ZIKV infection of mosquito cells by enhancing cell entry, it either had little impact on ZIKV infection on certain human cells or decreased infection through entry factor DC-SIGN. In conclusion, we define the roles of individual residues of ZIKV envelope protein, which contribute to ZIKV replication fitness in human and mosquito cells.\n\nHighlightsO_LIGene-wide mapping of functional residues of E protein in human and mosquito cells.\nC_LIO_LIMutations affecting N-linked glycosylation display the most dramatic difference.\nC_LIO_LIN-linked glycosylation decreases ZIKV entry into mosquito cells.\nC_LIO_LIN-linked glycosylation is important for DC-SIGN mediated infection of human cells.\nC_LI

microbiology↗