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Aims: To obtain the high‐yield strain of fusidic acid, which is produced from fungus Fusidium coccineum and is the only fusidane‐type antibiotic that has been used clinically, and confirm the changes in the transcription levels involved in increasing its production. Methods and Results: By using the atmospheric and room temperature plasma mutagenesis technology, a high‐yield mutant strain of fusidic acid‐producing fungus F. coccineum was obtained. Using the genomic analysis of the original strain based on biosynthetic pathways of ergosterol and helvolic acid, we demonstrate that the pathway involved in the biosynthesis of 2,3‐oxidosqualene from acetyl coenzyme A was shared by fusidic acid and ergosterol, and fusidic acid was finally synthesized by the catalysis of multiple cytochrome P450s and short‐chain dehydrogenase/reductase from 2,3‐oxidosqualene. Then, through the transcriptomic analysis of the original and mutagenized strain, it revealed that the proposed pathway from sucrose to fusidic acid was the most significantly up‐regulated in the transcription levels of the mutant strain. Conclusions: The changes in the transcription levels of fusidic acid during its biosynthesis might result in high‐yield of fusidic acid in the mutant strain. This is the first report on the whole biosynthetic pathway of fusidic acid in F. coccineum. Significance and Impact of the Study: This study obtain the genetic basis for the biosynthesis of fusidic acid which could be beneficial for the molecular modifications of F. coccineum to further increase its yield by fermentation in future, and established the foundation to reveal the mechanism of the high‐yield of the mutant strain. [ABSTRACT FROM AUTHOR]

Understanding views of patients on biologics for psoriasis amid the COVID-19 pandemic This study assessed psoriasis patients' understanding of the safety of biologic use during the C19 pandemic and their perception of various information sources. Biologics target and inhibit specific cytokines, thereby suppressing the immune system and manifestation of psoriasis. [Extracted from the article]

An 8-week feeding trial was conducted to determine the optimal dietary arginine requirement for juvenile swimming crab Portunus trituberculatus. Six isonitrogenous and isolipidic experimental diets were formulated to contain graded arginine levels which ranged from 15.9 to 33.0 g kg−1. Each diet was randomly assigned to triplicate groups of 60 juvenile swimming crabs (4.72 ± 0.12 g). The results indicated that dietary arginine had significant effects on weight gain ( WG), specific growth rate ( SGR), protein productive value, feed efficiency and protein efficiency ratio. Weight gain and SGR significantly increased with the dietary arginine increasing from 15.9 to 27.4 g kg−1, while with the further increasing from 27.4 to 33.0 g kg−1, WG and SGR did not increase significantly. Maximum arginine, proline and total essential amino acid contents in muscle were observed in 27.4 g kg−1 group diet. The swimming crab fed the diet with lower dietary arginine level showed higher AST and lower ALT in the serum. Crab fed with the lower dietary arginine level had significantly lower ALT in the serum than the other groups. Haemolymph indexes were significantly affected by the dietary arginine level except for the cholesterol concentration, and the highest values were all found in 27.4 g kg−1 group diet. The two slope broken-line model using SGR showed that the optimal dietary arginine requirement was 27.7 g kg−1 of the dry matter (56.0 g kg−1 dietary protein) for juvenile swimming crab. [ABSTRACT FROM AUTHOR]

Discusses magnetostratigraphic results on two exposed parallel sections of lacustrine sediments at Xiaochangliang in the Nihewan Basin, north China. Contentious topic in the study of human evolution; Age of Paleolithic stolen artifacts.

Linked Article: Obeid et al. Br J Dermatol 2021; 184:1023–1032. [ABSTRACT FROM AUTHOR]

The article offers study on the use of absolute risk measurements in observational dermatology studies. Topics discussed include information on the importance of absolute term for clinical and public health decision-making; discussions on the clinical recommendations for screening tests or medication modifications; and the information on the evaluation of psoriasis comorbidities.