Biography
The focus of Baisuo Zhao research is bacterial taxonomy and microbial physiology, Molecular mechanisms of gene expression and mutagenesis. He is also interested in studies of molecular microbial ecology including the genetic and the functional diversity of microbial communities. His third research interest on Microbial Genomics & Metagenomics involves in genome analysis of pure isolates and metagenomics from extreme conditions, reactors etc.
Abstract
The anaerobic haloalkaliphile Alkalitalea saponilacus SC/BZ-SP2T could utilize xylan as sole carbon source and produce propionate as the main fermentation product. The xylanase activity from A. using the combined substrates of 0.4% (w/v) sucrose + 0.1% (w/v) birch xylan was 3.2-fold than that of 0.5% (w/v) sucrose or 0.5% (w/v) birch xylan. The xylanse is halo-stable as it exhibited optimal activity at a broad range of 2-6% NaCl. Its activity was inhibited by Cu2+, Fe3+, Ni2+, Al3+, Mn2+, Co2+, Zn2+ and Ca2+ while increased 1.16-fold with the addition of Tween 20. In order to get a deep understanding of the potential genetic mechanisms of xylanase secretion and adaptive saline-alkali tolerance, the complete genome sequence of strain SC/BZ-SP2T was performed with the Pacbio SMRT and Illumina Misseq platforms. The genome contained one chromosome, with the total size of 4,775,573 bps, and the G+C content of this strain was 39.27%. A number of genes related to xylan degradation and its complete xylan degradation pathway, xyn A gene of xylanase belonging to a glycoside hydrolase (GH) family 10 and its neighborhood genes were systematically identified. Furthermore, various genes involved in biosynthesis and transportation of osmolytes, as well as genes encoding monovalent cation/proton antiporters, multi-subunit sodium/ proton antiporters, F0F1-ATP synthases, H+-transporting ATPases, Na+/solute symporters and K+ transport systems were predicted. This genome sequence provides molecular information and elucidation for halo-stable xylanase production, and will be used in the biotechnology.
Biography
Andre Freire Cruz had focused on evaluation of soil microbial status as indicator of sustainability. He has worked with many agricultural soils, recently has concentrated on fruit orchards in Japan and other countries especially concerning on analysis of microbial growth and activity. He has used many methods to evaluate the soil biology, but actually most of his researches are using metagenome analysis of bacterial and fungal genes and their relation with other soils properties.
Abstract
The microbial community evaluation constitutes an essential topic to access the soil health conditions, with special regard to the operational taxonomic units (OTU). This data can easily represent the soil bacterial condition and also might distinguish many kinds of environment, such as urban areas, and agricultural soils. As a criterion to set up a “finger-print†for agricultural soils in terms of microbial community, metagenomic profiles from crops and fruit soils had their OTU analyzed after the normalizing their abundance where the sum of each sample was equivalent to 1. The bacterial and fungal genes were the target region evaluated by principal component analysis (PCA). Although some dominant taxonomic groups were constantly present in most of the soils, the OTU within the bacterial and fungal communities were specific according to the land use type (crops or fruits) i.e. each one had a remarkable difference in terms of OTU. Hokkaido prefecture contained most of specific groups, whereas other prefectures were more diverse. Similar profile was found in fungal genes. Within the bacterial genes a few number of OTUs made possible to separate crops and fruit soils, however for the fungal ones a large number was necessary for the same goal. The bacterial representative genera were Nitrospira (involved with Nitrogen cycling) and Arthrobacter. Whereas the Fusarium was the most important fungus in terms of OTU bioindicator.