Alanyl-transfer ribonucleic acid synthetase 2 gene mutation producing leukodystrophy: a case report / 中华神经科杂志

Objective:To investigate the clinical features, imaging features and gene mutation of a paitent with alanyl-transfer ribonucleic acid synthetase 2 (AARS2) gene mutation- related leukodystrophy and further improve the understanding of this rare disease.Methods:Clinical data of a patient with leukodystrophy associated with AARS2 gene mutation diagnosed in October 2020 at Xiamen Hospital of Beijing University of Chinese Medicine and Huashan Hospital of Fudan University were collected.Results:The male patient, 25 years old, was admitted with the clinical manifestations, including chronic onset dyskinesia, ataxia, nystagmus and psoriasis. Head magnetic resonance imaging (MRI) showed bilateral white matter lesions and cerebellar atrophy. Spine MRI showed vertebral body incomplete fusion. Gene detection showed heterozygous compound AARS2 gene mutation [c.985C>T chr6:44275041(p.R329C) and c.452T>C chr6:44279256(p.M151T)].Conclusions:AARS2 gene mutation-related leukodystrophy is a rare mitochondrial disease in clinical practice. The patient presented with progressive motor deficits in the lower limbs, ataxia, relatively retained cognitive function. MRI revealed abnormal symmetry of corpus callosum and bilateral paraventricular white matter. Heterozygous compound AARS2 gene mutations [c.985C>T chr6:44275041 (p.R329C) and c.452T>C chr6:44279256 (p.M151T)] are one of the pathogenic factors leading to hereditary leukodystrophy.

Molecular ecological network reveals the response of metallurgical microorganisms to energy substrates / 生物工程学报

By analyzing the shift of microbial communities under different iron/sulfur ratios, the response of metallurgical microorganisms to energy substrates was investigated based on molecular ecological networks. High-throughput sequencing of microbial samples from different domesticated batches was conducted to analyze the changes in community composition, alpha and beta diversity. Based on the molecular ecological network, the interactions between microorganisms under different iron/sulfur ratios were explored. Keystones were identified to analyze the community response to energy substrates. In the process of domestication based on different energy substrates, the dominant species in the in iron-rich and sulfur-less community were Acidithiobacillus ferrooxidans and A. ferriphilus. A. thiooxidans accounted for up to 90% in the sulfur-rich and iron-less community after 3 domesticating batches. The results of alpha and beta diversity analysis show that the domestication process of sulfur-rich and iron-less substrates reduced the diversity of microbial communities. Molecular ecological network analysis shows that the keystones were all rare species with low abundance. During the domestication by sulfur-rich and iron-less energy substrates, the bacterial species had a closer symbiotic relationship and the community was more stable. Through this domestication experiment, the impact of different energy substrates on microbial aggregation was clarified. Domesticating metallurgical microorganisms by using sulfur-rich and iron-less energy substrates made the microbial colonies to be more stable, which was conducive to the oxidation of iron and sulfur, promoting the dissolution of sulfide minerals. Our findings provide a reference for the directional domestication of metallurgical microorganisms.