Biology subjects

Lon, J. R.

Publications and source records attributed to Lon, J. R..

7 recordsLinked to original sources

bioRxiv2024

Microbial Weathering Analysis of Anshun Tunbao Artifacts

AbstractsCultural heritages are the crystallization of human technology, culture and embody the efforts of many craftsmen in ancient times. Wooden cultural heritages are affected by their own materials, and are very susceptible to microbial invasion under suitable temperature and humidity conditions. This project mainly studies the microbial weathering of the core wood carving masks and wooden ancient stage in Anshun Tunpu cultural heritage, and uses scanning electron microscopy, high-throughput sequencing and traditional culture methods to analyze the characteristics of their microbial communities, and finds that the bacteria represented by Pseudomonas, Paenibacillus and Stenotrophomonas, and the fungi represented by Cladosporium, Alternaria and Aspergillus, are the core microorganisms shared by indoor and outdoor cultural heritage. The dominant genera such as Pseudomonas, Stenotrophomonas, and Cladosporium showed lignocellulose deradation ability. By cultivating insect eggs extracted from sampled specimens and analyzing the correlation with surface microbiota, we verified the role of insect eggs as vectors in dispersing key microbial communities. We speculate that these insects are likely to be Anobiidae family. Furthermore, by comparing the microbial compositions under different climatic conditions, we validated the influence of temperature, humidity, vegetation diversity, and microbial intrinsic structures on microbial growth. Therefore, monitoring the surrounding environment is crucial in microbial weathering studies and cultural heritage preservation efforts. This study pioneered the investigation of microbial weathering aspects on unique heritage of the Tuenbao culture, emphasizing the importance of preserving distinctive ethnic cultures. Additionally, it presented a case study on the microbial weathering of wooden artifacts in karst landscape environments.

microbiology↗

bioRxiv2023

Analysis of Biodeterioration on Ancestral Halls with Different Visitor Flow Rates Using Amplicon Sequencing and Conventional Culturing Methods

AbstractWooden buildings are facing biodeterioration due to natural weathering. Ancestral halls are traditional Chinese wooden architecture with high artistic value. The research analyzed the microbial diversity of nine ancestral halls in Guangdong Province under subtropical monsoon climates. With amplicon sequencing, we found a common core microorganism group, including Bacillus, Pseudomonas, Paenibacillus, Acinetobacter, Toxicocladosporium, Cladosporium, Aspergillus, and Epicoccum. A total of 8 different species of bacteria and 7 different species of fungi were isolated from Chen Clan Ancestral halls, most of which were proven to be capable of degrading cellulose or lignin. The comparison between damaged and undamaged sites (whether the paint coating is flaked off) revealed similar microbial compositions but with differing abundances. Firmicutes and Ascomycota dominated damaged surfaces, while Proteobacteria and Actinobacteria prevailed in undamaged ones. Notably, Cladosporium, widely present in both sites, emerged as the primary cellulose-degrading genus. Given the similar microbial compositions between damaged and undamaged sites, it is suggested that using paint alone as the exclusive means to protect bare wood is insufficient. Apparent correlation between microorganisms on wooden surfaces and humans showed that the increase of visitor flow rates might impact the microbiota composition on cultural relics. We evaluated the effect of four representative biocides and determined the feasibility of low-concentration Isothiazolinone. This research facilitates a basic understanding of the microbial weathering of ancestral halls and add significant reference for preserving wooden structures.

microbiology↗

bioRxiv2021

AutoVEM2: a flexible automated tool to analyze candidate key mutations and epidemic trends for virus

In our previous work, we developed an automated tool, AutoVEM, for real-time monitoring the candidate key mutations and epidemic trends of SARS-CoV-2. In this research, we further developed AutoVEM into AutoVEM2. AutoVEM2 is composed of three modules, including call module, analysis module, and plot module, which can be used modularly or as a whole for any virus, as long as the corresponding reference genome is provided. Therefore, its much more flexible than AutoVEM. Here, we analyzed three existing viruses by AutoVEM2, including SARS-CoV-2, HBV and HPV-16, to show the functions, effectiveness and flexibility of AutoVEM2. We found that the N501Y locus was almost completely linked to the other 16 loci in SARS-CoV-2 genomes from the UK and Europe. Among the 17 loci, 5 loci were on the S protein and all of the five mutations cause amino acid changes, which may influence the epidemic traits of SARS-CoV-2. And some candidate key mutations of HBV and HPV-16, including T350G of HPV-16 and C659T of HBV, were detected. In brief, we developed a flexible automated tool to analyze candidate key mutations and epidemic trends for any virus, which would become a standard process for virus analysis based on genome sequences in the future. HighlightsO_LIAn automatic tool to quickly analyze candidate key mutations and epidemic trends for any virus was developed. C_LIO_LIOur integrated analysis method and tool could become a standard process for virus mutation and epidemic trend analysis based on genome sequences in the future. C_LIO_LIN501Y with the other 16 highly linked mutation sites of SARS-CoV-2 in the UK and Europe were further confirmed, and some valuable mutation sites of HBV and HPV-16 were detected. C_LI

genomics↗

bioRxiv2021

Molecular dynamics simulation study of effects of key mutations in SARS-CoV-2 on protein structures

SARS-CoV-2 has been spreading rapidly since 2019 and has produced large-scale mutations in the genomes. The mutation in genes may lead to changes in protein structure, which would have a great impact on the epidemiological characteristics. In this study, we selected the key mutations of SARS-CoV-2 from a real-time monitoring tool, including D614G, A222V, N501Y, T716I, S982A, D1118H of spike (S) protein, and performed molecular dynamics (MD) simulations on single-site mutant D614G, double-site mutant D614G&A222V and penta-site mutant N501Y&D614G&T716I&S982A&D1118H to investigate their effects on protein structure and stability using molecular dynamics (MD) simulations. The results suggested that D614G improved the stability of S protein, while D614G&A222V and N501Y&D614G&T716I&S982A&D1118H showed an increased solvent accessible surface area and they might enhance the ability of protein to react with the outside environment. Our findings could complement the mechanistic link between genotype--phenotype--epidemiological characteristics in the study of SARS-CoV-2. We also found no significant difference between the antigenicity of S protein and the mutants through Ellipro, which may reference for vaccine development and application.

bioinformatics↗

bioRxiv2020

Real-time monitoring epidemic trends and key mutations in SARS-CoV-2 evolution by an automated tool

With the global epidemic of SARS-CoV-2, it is important to monitor the variation, haplotype subgroup epidemic trends and key mutations of SARS-CoV-2 over time effectively, which is of great significance to the development of new vaccines, the update of therapeutic drugs, and the improvement of detection reagents. The AutoVEM tool developed in the present study could complete all mutations detections, haplotypes classification, haplotype subgroup epidemic trends and key mutations analysis for 131,576 SARS-CoV-2 genome sequences in 18 hours on a 1 core CPU and 2G internal storage computer. Through haplotype subgroup epidemic trends analysis of 131,576 genome sequences, the great significance of the previous 4 specific sites (C241T, C3037T, C14408T and A23403G) was further revealed, and 6 new mutation sites of highly linked (T445C, C6286T, C22227T, G25563T, C26801G and G29645T) were discovered for the first time that might be related to the infectivity, pathogenicity or host adaptability of SARS-CoV-2. In brief, we proposed an integrative method and developed an efficient automated tool to monitor haplotype subgroup epidemic trends and screen out the key mutations in the evolution of SARS-CoV-2 over time for the first time, and all data could be updated quickly to track the prevalence of previous key mutations and new key mutations because of high efficiency of the tool. In addition, the idea of combinatorial analysis in the present study can also provide a reference for the mutation monitoring of other viruses.

genomics↗

bioRxiv2020

Evolution and molecular characteristics of SARS-CoV-2 genome

ObjectivesTo reveal epidemic trend and possible origins of SARS-CoV-2 by exploring its evolution and molecular characteristics based on a large number of genomes since it has infected millions of people and spread quickly all over the world. MethodsVarious evolution analysis methods were employed. ResultsThe estimated Ka/Ks ratio of SARS-CoV-2 is 1.008 or 1.094 based on 622 or 3624 SARS-CoV-2 genomes, and the time to the most recent common ancestor (tMRCA) was inferred in late September 2019. Further 9 key specific sites of highly linkage and four major haplotypes H1, H2, H3 and H4 were found. The Ka/Ks, detected population size and development trends of each major haplotype showed H3 and H4 subgroups were going through a purify evolution and almost disappeared after detection, indicating H3 and H4 might have existed for a long time, while H1 and H2 subgroups were going through a near neutral or neutral evolution and globally increased with time. Notably the frequency of H1 was generally high in Europe and correlated to death rate (r>0.37). ConclusionsIn this study, the evolution and molecular characteristics of more than 16000 genomic sequences provided a new perspective for revealing epidemiology of SARS-CoV-2.

bioinformatics↗

bioRxiv2020

Prediction and Evolution of B Cell Epitopes of Surface Protein in SARS-CoV-2

The discovery of epitopes is helpful to the development of SARS-CoV-2 vaccine. The sequences of the surface protein of SARS-CoV-2 and its proximal sequences were obtained by BLAST, the sequences of the whole genome of SARS-CoV-2 were obtained from the GenBank. Based on the NCBI Reference Sequence: NC_045512.2, the conformational and linear B cell epitopes of the surface protein were predicted separately by various prediction methods. Furthermore, the conservation of the epitopes, the adaptability and other evolutionary characteristics were also analyzed. 7 epitopes were predicted, including 5 linear epitopes and 2 conformational epitopes, one of the linear and one of the conformational were coincide. The epitope D mutated easily, but the other epitopes were very conservative and the epitope C was the most conservative. It is worth mentioning that all of the 6 dominated epitopes were absolutely conservative in nearly 1000 SARS-CoV-2 genomes, and they deserved further study. The findings would facilitate the vaccine development, had the potential to be directly applied on the treatment in this disease, but also have the potential to prevent the possible threats caused by other types of coronavirus.

bioinformatics↗