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Morchella is a genus of fungi with the ability to concentrate Cd both in the fruit-body and mycelium. However, the molecular mechanisms conferring resistance to Cd stress in Morchella are unknown. Here, RNA-based transcriptomic sequencing was used to identify the genes and pathways involved in Cd tolerance in Morchella spongiola. 7444 differentially expressed genes (DEGs) were identified by cultivating M. spongiola in media containing 0.15, 0.90, or 1.50 mg/L Cd2+. The DEGs were divided into six sub-clusters based on their global expression profiles. GO enrichment analysis indicated that numerous DEGs were associated with catalytic activity, cell cycle control, and the ribosome. KEGG enrichment analysis showed that the main pathways under Cd stress were MAPK signaling, oxidative phosphorylation, pyruvate metabolism, and propanoate metabolism. In addition, several DEGs encoding ion transporters, enzymatic/non-enzymatic antioxidants, and transcription factors were identified. Based on these results, a preliminary gene regulatory network was firstly proposed to illustrate the molecular mechanisms of Cd detoxification in M. spongiola. These results provide valuable insights into the Cd tolerance mechanism of M. spongiola and constitute a robust foundation for further studies on detoxification mechanisms in macrofungi that could potentially lead to the development of new and improved fungal bioremediation strategies.

Goji, a renowned traditional Chinese medicine and food source, is characterized by a long fruiting period. This study was conducted to investigate the variations in nutritional quality of goji berries across different harvest stages by utilizing widely targeted metabolome and transcriptome. The results showed that goji berries of the first harvest stage had advantages in terms of size and metabolic levels, and there was little difference in sugars and organic acids levels. Within significantly enriched phenylpropanoid and flavonoid pathways, chlorogenic acid, and its positional isomers (neochlorogenic acid and cryptochlorogenic acid) increased significantly along with P‐coumaroyl quinic acid as the harvest stages progressed, while the other bioactive DEMs including scopoletin, scopolin, naringenin, and pruning exhibited a decreasing trend. The key DEGs encoding PAL, HCT, 4CL, C4H, TOGT1, and C12RT1 were suggested to regulate the variations of these DEMs. Furthermore, six oxidative metabolites enriched in alpha‐linolenic acid and linoleic acid metabolism pathways all peaked at the second harvest stage. Climate or plant weakening is suggested as potential factors influencing the metabolic and transcriptomic changes in goji berries. This study provides a fresh perspective on understanding the accumulation of metabolites and their molecular mechanisms in goji at different harvest stages in the Qaidam Basin and can be used to guide goji production and processing. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a group of highly toxic organic pollutants. At present, there has only been limited research into PAH contamination in Tangxun Lake and Dong Lake, which are the first and second largest urban inland lakes in China, respectively. This study investigated the concentration, spatial distribution, sources, and ecological risks of PAHs in the water from Dong Lake and Tangxun Lake. The focus of this study is to use models to analyze the sources of PAHs, as well as their potential toxicity to humans, in the water bodies of Dong Lake and Tangxun Lake. This study performed liquid–liquid extraction to extract PAHs from lake water samples using dichloromethane and then used gas chromatography–mass spectrometry (GC-MS) to quantitatively analyze the PAHs in the samples. The total concentration of the ∑16PAHs showed high variability among different sampling points, ranging from 12.92 to 989.09 ng/L, with an arithmetic mean of 121.97 ng/L. The composition of the ∑16PAHs was mainly concentrated at a low molecular weight (>70%). The molecular distributions of PAH studies, combined with positive matrix factorization (PMF), indicate that oil and coal combustion are the main sources of PAHs in Dong Lake and Tangxun Lake. The model of PMF succeeded in identifying and quantifying five sources with similar contributions: the combustion of petroleum products, heavy oil burning, coal combustion, traffic emissions, and natural gas and oil combustion mixed. According to toxicity equivalency (TEQ) and lifelong cancer risk (ILCR) research, PAHs from traffic sources in the environment may be more toxic, and the potential carcinogenic risk of PAH pollution to humans in Tangxun Lake and Dong Lake water bodies is relatively inferior. [ABSTRACT FROM AUTHOR]

Objective: The objective of this research was to study plant cell wall degradation enzymes from Fusarium sp. Q7-31T., Methods: Strain was cultured in liquid medium with 1% (W/V) peptone as nitrogen source, 0.5% (W/V) oat straw as carbon source, 120 r/min shaking at 20 °C for 3 days. The endoglucanase Egn21 was purified by using Sephacry S-100 chromatography and DEAE-sepharose ion-exchange column chromatography. Then the enzymatic properties and MADIL-TOF-TOF identification were analyzed., Results: The molecular weight and isoelectric point (pI) of Egn21 was 44.25 kDa and 4.91, respectively. Egn21 had optimal activity with carboxymethyl cellulose at 40 °C and pH 6.0, stable at 45 °C and pH between 5.0 and 8.0, inhibited by Fe2+, Ca2+, K+, Na+, Mn2+ and inactivated by Hg2+, whereas Co2+, Zn2+ and Mg2+ had no effect., Conclusion: The enzymatic properties and MADIL-TOF-TOF results suggested that Egn21 belongs to GH5 family.

Objective: The endoglucanase from Fusarium sp. Q7-31T was isolated, purified, identified and characterized to provide data for enzyme system of Fusarium sp. . [Methods] Strain was cultured in liquid fermentation with oat straw as carbon source, the endoglucanase was purified by using Sephacry S-100 chromatography and DEAE-sepharose ion-exchange column chromatography and the enzymatic properties were studied. The protein was identified using MADIL-TOF-TOF., Results: An endoglucanase was purified and named Egn20. The molecular weight was 55.37 kDa and isoelectric point (pI) was 7.44. Egn20 had optimal activity with carboxymethyl cellulose at 40 degrees C and pH 6.0, stabilized at 45 degrees C and pH 5.0 - 7.0, activated by Fe2+, inhibited by Na+, Ca2+, Mg2+, Zn2+, K+ and inactivated by Hg2+. The enzymatic properties and MADIL-TOF-TOF results suggested that Egn20 belongs to GH7 family., Conclusion: Our results may provide important data for the study of Fusarium sp. enzyme system.