Polyketides have been widely used clinically due to their significant biological activities, but the needed structural and functional diversity cannot be achieved by common chemical synthetic methods. The tool of comb...Polyketides have been widely used clinically due to their significant biological activities, but the needed structural and functional diversity cannot be achieved by common chemical synthetic methods. The tool of combinatorial biosynthesis provides the possibility to produce "unnatural" natural drugs, which has achieved initial success. This paper provides an overview for the strategies of combinatorial biosynthesis in producing the structural and functional diversity of polyketides, including the redesign of metabolic flow, polyketide synthase(PKS) engineering, and PKS post-translational modification. Although encouraging progress has been made in the last decade, challenges still exist regarding the rational combinatorial biosynthesis of polyketides. In this review, the perspectives of polyketide combinatorial biosynthesis are also discussed.展开更多
In accordance to National Commodity Policy （2011-2020）, Malaysian government targets at expending the pepper cultivated area from the current 16,331 ha to 20,110 ha by year 2020. Based on a planting density of 2,000...In accordance to National Commodity Policy （2011-2020）, Malaysian government targets at expending the pepper cultivated area from the current 16,331 ha to 20,110 ha by year 2020. Based on a planting density of 2,000 vines/ha, there will be an urgent need of 7.588 million cuttings for the next five years in order to achieve this target. However, shortages of planting materials, low productivity and occurrence of pests and diseases remain as the major challenge of pepper industry nowadays. Therefore, a novel farming innovation, namely W-configuration cultivation method has been developed to ensure high production of planting materials for large-scale pepper cultivation and at the same time to maximize land use in pepper farm. A field evaluation was conducted to compare the cutting production among W-configuration, V-configuration and traditional cultivation method. W-configuration recorded the highest mean number of pepper cuttings produced with 11.97 cuttings per vine in every pruning cycle, or equivalent to 71% of increment as compared to 7.00 cuttings per vine produced from the traditional planting method. Meanwhile, V-configuration produced 8.91 of mean cuttings, which are significantly lower than those produced by W-configuration method and yet comparable to traditional method. Based on return on investment （ROI） analysis, implementation of W-configuration cultivation method was able to achieve 35% of return per cycle of planting within two years for the first cycle and upsurged to approximately 355% for the subsequence cycle. Furthermore, this novel innovation also out-yielded traditional planting method by 75.27% for the first and second year of green berry production. The ROI analysis proved the feasibility of this newly developed cultivation method to create potential new income for pepper smallholders in Malaysia, who traditionally cultivate pepper for its peppercorn production. This study also enlightened the thorough planting procedures of W-configuration cultivation method mainly for pepper cutting production.展开更多
基金supported by the Major Research Plan of Tianjin(No.16YFXTSF00460)
文摘Polyketides have been widely used clinically due to their significant biological activities, but the needed structural and functional diversity cannot be achieved by common chemical synthetic methods. The tool of combinatorial biosynthesis provides the possibility to produce "unnatural" natural drugs, which has achieved initial success. This paper provides an overview for the strategies of combinatorial biosynthesis in producing the structural and functional diversity of polyketides, including the redesign of metabolic flow, polyketide synthase(PKS) engineering, and PKS post-translational modification. Although encouraging progress has been made in the last decade, challenges still exist regarding the rational combinatorial biosynthesis of polyketides. In this review, the perspectives of polyketide combinatorial biosynthesis are also discussed.
文摘In accordance to National Commodity Policy （2011-2020）, Malaysian government targets at expending the pepper cultivated area from the current 16,331 ha to 20,110 ha by year 2020. Based on a planting density of 2,000 vines/ha, there will be an urgent need of 7.588 million cuttings for the next five years in order to achieve this target. However, shortages of planting materials, low productivity and occurrence of pests and diseases remain as the major challenge of pepper industry nowadays. Therefore, a novel farming innovation, namely W-configuration cultivation method has been developed to ensure high production of planting materials for large-scale pepper cultivation and at the same time to maximize land use in pepper farm. A field evaluation was conducted to compare the cutting production among W-configuration, V-configuration and traditional cultivation method. W-configuration recorded the highest mean number of pepper cuttings produced with 11.97 cuttings per vine in every pruning cycle, or equivalent to 71% of increment as compared to 7.00 cuttings per vine produced from the traditional planting method. Meanwhile, V-configuration produced 8.91 of mean cuttings, which are significantly lower than those produced by W-configuration method and yet comparable to traditional method. Based on return on investment （ROI） analysis, implementation of W-configuration cultivation method was able to achieve 35% of return per cycle of planting within two years for the first cycle and upsurged to approximately 355% for the subsequence cycle. Furthermore, this novel innovation also out-yielded traditional planting method by 75.27% for the first and second year of green berry production. The ROI analysis proved the feasibility of this newly developed cultivation method to create potential new income for pepper smallholders in Malaysia, who traditionally cultivate pepper for its peppercorn production. This study also enlightened the thorough planting procedures of W-configuration cultivation method mainly for pepper cutting production.
