Enantioselective Construction of Quaternary Stereocenters via Cooperative Photoredox/Fe/Chiral Primary Amine Triple Catalysis.

The catalytic and enantioselective construction of quaternary (all-carbon substituents) stereocenters poses a formidable challenge in organic synthesis due to the hindrance caused by steric factors. One conceptually viable and potentially versatile approach is the coupling of a C-C bond through an outer-sphere mechanism, accompanied by the realization of enantiocontrol through cooperative catalysis; however, examples of such processes are yet to be identified. Herein, we present such a method for creating different compounds with quaternary stereocenters by photoredox/Fe/chiral primary amine triple catalysis. This approach facilitates the connection of an unactivated alkyl source with a tertiary alkyl moiety, which is also rare. The scalable process exhibits mild conditions, does not necessitate the use of a base, and possesses a good functional-group tolerance. Preliminary investigations into the underlying mechanisms have provided valuable insights into the reaction pathway.

Phosphine-Catalyzed 1,2-cis-Diboration of 1,3-Butadiynes.

Trialkyl phosphines PMe3 and PEt3 catalyze the 1,2-cis-diboration of 1,3-butadiynes to give 1,2-diboryl enynes. The products were utilized to synthesize 1,1,2,4-tetraaryl enynes using a Suzuki-Miyaura protocol and can readily undergo proto-deborylation.

Quality of life, household income, and dietary habits are associated with the risk of sarcopenia among the Chinese elderly.

BACKGROUND: Health-related quality of life (HRQoL), which can be influenced by various aspects, especially socioeconomic status and lifestyle, has been identified as an important predictor of the prognosis of older adults. Dietary habit, a major part of lifestyle, can affect the nutritional status, which is closely correlated with the development of geriatric syndromes in the elderly. AIMS: The aim of the study was to examine the association of HRQoL, socioeconomic status, and lifestyle with the risk and severity of sarcopenia, a geriatric syndrome characterized by progressive loss of skeletal muscle mass, strength and function. METHODS: A cross-sectional retrospective study with 2877 participants aged ≥65 years was performed. HRQoL was assessed using EuroQoL Five Dimensions questionnaire. Socioeconomic status was assessed by the educational attainment, occupation, and household income. Lifestyle was assessed using 12 items closely related to Chinese living habits. The information of daily dietary habits including tea, alcohol, type of diet, and volume of drinking water were collected. The associations of HRQoL, socioeconomic status, and lifestyle with the risk of sarcopenia were examined by multivariate regression logistical analysis. The potential causal role of age, body mass index, and waist circumference in the effect of HRQoL on sarcopenia risk was analyzed by causal mediation analysis. RESULTS: High HRQoL [adjusted odds ratio (OR) =0.85, 95% confidence interval (CI) =0.69-0.95, P=0.034] and household income levels (adjusted OR =0.74, 95% CI =0.57-0.95, P=0.019) were inversely associated with the risk of sarcopenia. Meanwhile, more consumption of spicy food (adjusted OR =1.34, 95% CI =1.09-1.81, P =0.037) and occasionally drinking (adjusted OR =1.46, 95% CI =1.07-2.00, P =0.016, as compared to those never drinking) were associated with higher risk of sarcopenia, while skipping breakfast occasionally (adjusted OR =0.37, 95% CI =0.21-0.64, P <0.001, as compared to those eating breakfast every day) and less consumption of salt (adjusted OR =0.71, 95% CI =0.52-0.96, P =0.026, as compared to those consuming high amount of salt) were associated with lower risk of sarcopenia. Further causal mediation analysis aimed to explore how much age, body mass index, and waist circumference might explain the effect of HRQoL on the risk of sarcopenia showed that the estimated proportion that mediated the effect of HRQoL on the risk of sarcopenia by age was 28.0%. CONCLUSIONS: In summary, our findings demonstrate that low levels of HRQoL and household income, more intake of salt and spicy food, and occasional intake of alcohol are correlated with higher risk of sarcopenia, while skipping breakfast occasionally is associated with lower risk of sarcopenia in a Chinese population of older adults.

Nickel-Catalyzed Highly Selective Radical C-C Coupling from Carboxylic Acids with Photoredox Catalysis.

The selective coupling of two different radicals is a long-standing challenge due to the process occurring statistically. Generally, the cross-coupling selectivity is achieved by the persistent radical effect (PRE), resulting in limited radical precursors. In this paper, a highly selective cross-coupling of alkyl radicals with acyl radicals to construct C(sp2)-C(sp3) bonds, or with alkyl radicals to construct C(sp3)-C(sp3) bonds have been achieved with the readily available carboxylic acids and their derivatives (NHPI ester) as coupling partners. The success originates from the use of tridentate ligand (L1) to enable radical cross-coupling process to Ni-mediated organometallic mechanism. This protocol offers a facile and flexible access to structurally diverse ketones (up to 90% yield), and also a new solution for the challenging double decarboxylative C(sp3)-C(sp3) coupling. The broad utility and functional group tolerance are further illustrated by the late-stage functionalization of natural-occurring carboxylic acids and drugs.

Gold-Manganese Bimetallic Redox Coupling with Light.

The classical Au(I)/Au(III) redox couple chemistry has been limited to constructing C-C and C-X bonds, and thus, the exploration of the elementary reaction of gold redox coupling is very significant to enrich its organometallic features. Herein, we report the first visible-light-mediated, external oxidant-free Au(I)/Au(III) redox couple using commercially available Mn2(CO)10 to generate Mn-Au(III)-Mn intermediates for bimetallic redox coupling. A wide range of structurally diverse heterodinuclear and polynuclear L-Au(I)-Mn-L' complexes (19 examples, up to >99% yields) are readily constructed, providing a robust strategy for the concise construction of Au-Mn complexes under mild reaction conditions. The mechanistic studies together with DFT calculations support the radical oxidative addition of •Mn(CO)5 to gold and bimetallic reductive elimination mechanisms from highly active Mn-Au(III)-Mn species, representing an important step toward an elementary reaction in gold chemistry research. Furthermore, the resulting Au-Mn complexes exhibit unique catalytic activity, with which divergent reductive coupling of nitroarenes can readily afford azoxybenzenes, azobenzenes, and hydrazobenzenes in moderate to good yields.

Site-Selective Arylation of Carboxamides from Unprotected Peptides.

The amidated peptides are an important class of biologically active compounds due to their unique biological properties and wide applications as potential peptide drugs and biomarkers. Despite the abundance of free amide motifs (Asn, Gln, and C-terminal amide) in native peptides, late-stage modification of the amide unit in naturally occurring peptides remains very rare because of the intrinsically weak nucleophilicity of amides and the interference of multiple competing nucleophilic residues, which generally lead to undesired side reactions. Herein, chemoselective arylation of amides in unprotected polypeptides has been developed under an air atmosphere to afford the N-aryl amide peptides bearing various functional motifs. Its success relies on the combination of gold catalysis and silver salt to differentiate the relative inert amide among a collection of reactive nucleophilic amino acid residues (e.g., -NH2, -OH, and -COOH), favoring the C-N bond coupling toward amides over other more nucleophilic groups. Experimental and DFT studies reveal a crucial role of the silver cation, which serves as a transient coordination mask of the more reactive reaction sites, overcoming the inherently low reactivity of amides. The excellent biocompatibility of this strategy has been applied to functionalize a wide range of peptide drugs and complex peptides. The application could be further extended to peptide labeling and peptide stapling.

Temporal effect of the spin-to-orbit conversion in tightly focused femtosecond optical fields.

Spin and orbital angular momenta are two of the most fundamental physical quantities that describe the complex dynamic behaviors of optical fields. A strong coupling between these two quantities leads to many intriguing spatial topological phenomena, where one remarkable example is the generation of a helicity-dependent optical vortex that converts spin to orbital degrees of freedom. The spin-to-orbit conversion occurs inherently in lots of optical processes and has attracted increasing attention due to its crucial applications in spin-orbit photonics. However, current researches in this area are mainly focused on the monochromatic optical fields whose temporal properties are naturally neglected. In this work, we demonstrate an intriguing temporal evolution of the spin-to-orbit conversion induced by tightly-focused femtosecond optical fields. The results indicate that the conversion in such a polychromatic focused field obviously depends on time. This temporal effect originates from the superposition of local fields at the focus with different frequencies and is sensitive to the settings of pulse width and central wavelength. This work can provide fundamental insights into the spin-orbit dynamics within ultrafast wave packets, and possesses the potential for applications in spin-controlled manipulations of light.

PT-Symmetric Feedback Induced Linewidth Narrowing.

Narrow linewidth is a long-pursued goal in precision measurement and sensing. We propose a parity-time symmetric (PT-symmetric) feedback method to narrow the linewidths of resonance systems. By using a quadrature measurement-feedback loop, we transform a dissipative resonance system into a PT-symmetric system. Unlike the conventional PT-symmetric systems that typically require two or more modes, here the PT-symmetric feedback system contains only a single resonance mode, which greatly extends the scope of applications. The method enables remarkable linewidth narrowing and enhancement of measurement sensitivity. We illustrate the concept in a thermal ensemble of atoms, achieving a 48-fold narrowing of the magnetic resonance linewidth. By applying the method in magnetometry, we realize a 22-times improvement of the measurement sensitivity. This work opens the avenue for studying non-Hermitian physics and high-precision measurements in resonance systems with feedback.

Constraints on Spin-Spin Velocity-Dependent Interactions.

The existence of exotic spin-dependent forces may shine light on new physics beyond the standard model. We utilize two iron shielded SmCo_{5} electron-spin sources and two optically pumped magnetometers to search for exotic long-range spin-spin velocity-dependent force. The orientations of spin sources and magnetometers are optimized such that the exotic force is enhanced and common-mode noise is effectively subtracted. We set direct limit on proton-electron interaction in the force range from 1 cm to 1 km. Our experiment represents more than 10 orders of magnitude improvement than previous works.

Simultaneous effects of aluminum exposure on the homeostasis of essential metal content in rat brain and perturbation of gut microbiota.

The theory of the brain-gut axis has confirmed that gut microbiota and metabolites are involved in the progression of neurodegenerative diseases through multiple pathways. However, few studies have highlighted the role of gut microbiota in cognitive impairment induced by aluminum (Al) exposure and its correlations with the homeostasis of essential metal content in the brain. To explore the relationship between alterations in the content of essential metals in the brain and relative abundance changes in gut microbiota induced by Al exposure, the Al, zinc (Zn), copper (Cu), iron (Fe), chromium (Cr), manganese (Mn), and cobalt (Co) content level in the hippocampus, olfactory bulb, and midbrain tissue were measured by inductively coupled plasma mass spectrometry (ICP-MS) methods after Al maltolate was intraperitoneally injected every other day for exposed groups. Then the unsupervised principal coordinates analysis (PCoA) and linear discriminant analysis effect size (LEfSe) were used to analyze the relative abundance of the gut microbiota community and the structure of the gut microbiome. Finally, the correlations between gut microbiota composition and essential metal content in the different exposure groups were explored by using the Pearson correlation coefficient method. Based on the results, we indicated that the content of Al in the hippocampus, olfactory bulb, and midbrain tissue was increased and then decreased with the increasing exposure duration, with peaks occurring between 14 and 30 days. Concomitantly, Al-exposure decreased the Zn, Fe, and Mn levels in these tissues. 16 S rRNA gene sequencing results indicated that significant differences in the intestinal microbial community structure at the phylum, family, and genus levels were found in the Day 90 exposed group compared with the Day 7 exposed group. Ten enriched species in the exposed group were identified as markers at the three levels. Furthermore, ten bacteria at the genus level were identified to have a significantly strong correlation (r = 0.70-0.90) with Fe, Zn, Mn, and Co.

Spatial-temporal pattern of change in production-living-ecological space of Nanchong City from 2000 to 2020 and underlying factors.

This study analyzed the spatial-temporal change pattern and underlying factors in production-living-ecological space (PLES) of Nanchong City, China, over the past 20 years using historical land use data (2000, 2010, 2020). A land use transfer matrix was calculated from the historical land use maps, and spatial analysis was conducted to analyze changes in the land use dynamics degree, standard deviation ellipse, and center of gravity. The results showed that there was a rapid spatial evolution of the PLES in Nanchong from 2000 to 2010, followed by a stabilization in the second decade. The transfer of ecological-production space occurred mainly in the Jialing and Yilong River basins, while the reduction of production space and the increase of living space were most prominent in the intersection of three districts (Shunqing, Jialing, and Gaoping districts). The return of production-ecological space was observed in the south and northeast of Yingshan, and there was little notable transfer of other types. The distribution of production space in Nanchong evolved in a north-south to east-west trend, with the center of gravity moving from Yilong to Peng'an County. The living space and production space expanded in a north-south direction, and the center of gravity position was in Nanbu, indicating a more balanced growth or decrease in the last 20 years. The changes in the spatial-temporal pattern of PLES in Nanchong were attributed to the intertwined factors of national policies, economic development, population growth, and the natural environment. This study introduced a novel approach towards rational planning of land resources in Nanchong, which may facilitate more sustainable urban planning and development.

Merging Manganese and Iminium Catalysis: Selective Hydroalkenylation of Unsaturated Aldehydes and Ketones.

The use of synergistic catalytic strategy can usually circumvent the intrinsic limitations of one catalytic system. In this communication, we disclose a cooperative catalysis strategy of manganese and iminium catalysis to realize selective hydroalkenylation of unsaturated aldehydes and ketones. Its success stems from the LUMO activation of unsaturated carbonyl compounds with secondary amines as the organocatalyst and the synergistic HOMO activation of alkenylboronic acids with Mn2 (CO)8 Br2 . This protocol exhibits several synthetic advances, e.g., simple operation, good functional group compatibility and good regioselectivity. The theoretical calculation indicates the migratory insertion followed by demetallation-isomerization process is kinetically more favorable than Michael-like nucleophilic addition. The use of proline-derived organocatalyst can deliver the desired products in moderate enantioselectivity.

Trinuclear Gold-Catalyzed 1,2-Difunctionalization of Alkenes.

Activated alkyl halides have been extensively explored to generate alkyl radicals with Ru- and Ir- photocatalysts for 1,2-difunctionalization of alkenes, but unactivated alkyl bromides remain challenging substrates due to their strong reduction potential. Here we report a three-component 1,2-difunctionalization reaction of alkenes, unactivated alkyl bromides and nucleophiles (e.g., amines and indoles) using a trinuclear gold catalyst [Au3 (tppm)2 ](OTf)3 . It can achieve the 1,2-aminoalkylation and 1,2-alkylarylation readily. This protocol has a broad reaction scope and excellent functional group compatibility (>100 examples with up to 96 % yield). It also affords a robust formal [2+2+1] cyclization strategy for the concise construction of pyrrolidine skeletons under mild reaction conditions. Mechanistic studies support an inner-sphere single electron transfer pathway for the successful cleavage of inert C-Br bonds.

Unlocking Migratory Insertion in Gold Redox Catalysis.

Exploration of elementary reactions in organometallic catalysis is an important method with which to discover new reactions. In this article, we report a gold(I)-catalyzed iodo-alkynylation of benzyne involving the merging of challenging migratory insertion and an oxidative addition process in gold catalytic cycle. A wide range of structurally diverse alkynyl iodides are good coupling partners in this iodo-alkynylation transformation. Both aliphatic and aromatic alkynyl iodides can react with benzynes smoothly to afford highly functionalized 1,2-disubstituted aromatics in moderate to good yields. Its good functional group compatibility and late-stage application of complex molecules demonstrate its synthetic robustness. Studies of the mechanism reveals the feasibility of oxidative addition and the DFT calculations demonstrate the possible migratory insertion of benzyne into AuIII -carbon bonds in the AuI /AuIII redox catalytic cycle, representing an important step towards an elementary reaction in gold chemistry research.

Dinuclear Gold-Catalyzed para-Selective C-H Arylation of Undirected Arenes by Noncovalent Interactions.

The regioselectivity of C-H functionalization is commonly achieved by directing groups, electronic factors, or steric hindrance, which facilitate the identification of reaction sites. However, such strategies are less effective for reactants such as simple monofluoroarenes due to their relatively low reactivity and the modest steric demands of the fluorine atom. Herein, we present an undirected gold-catalyzed para-C-H arylation of a wide array of monofluoroarenes using air-stable aryl silanes and germanes at room temperature. A high para-regioselectivity (up to 98 : 2) can be realized by utilizing a dinuclear dppm(AuOTs)2 (dppm=bis(diphenylphosphino)methane) as the catalyst and hexafluorobenzene as the solvent. This provides a general and practical protocol for the concise construction of structurally diverse para-arylated monofluoroarenes through C-H activation manner. It features excellent functional group tolerance and a broad substrate scope (>80 examples). Besides, this strategy is also robust for other simple monosubstituted arenes and heteroarenes. Our mechanistic studies and theoretical calculations suggest that para-C-H selectivity arises from highly electrophilic and structurally flexible dinuclear Ar-Au(III)-Au(I) species, coupled with noncovalent interaction induced by hexafluorobenzene.

Case report: a special case of cryptococcal infection-related inflammatory syndrome in a non-HIV infected and non-transplant patient.

BACKGROUND: Cryptococcal meningoencephalitis (CM) is a severe infection of central nervous system with high mortality and morbidity. Infection-related inflammatory syndrome is a rare complication of CM. Herein, we report a case of CM complicated by infection-related inflammatory syndrome. CASE PRESENTATION: A 42-year-old man with chronic hepatitis B presented with a 3-day history of aphasia and left hemiparesis at an outside medical facility. The brain magnetic resonance imaging (MRI) showed symmetric and confluent hyperintense signal abnormalities mainly located in the basal ganglia, internal capsule, external capsule, periventricular, corona radiata, frontal and temporal lobes. Cerebrospinal fluid (CSF) examinations revealed elevated leukocyte and protein. India ink staining was positive for Cryptococcus. CSF culture and metagenomic next-generation sequencing (mNGS) confirmed Cryptococcus neoformans. Initial response was observed with intravenous fluconazole (400 mg per day). However, 11 days later, he developed impaired consciousness and incontinence of urine and feces. A repeat brain MRI showed the lesions were progressive and enlarged. The patient was referred to our department at this point of time. Repeat CSF analysis (India ink staining, culture and mNGS) re-confirmed Cryptococcus. However, clinical worsening after initial improvement, laboratory examinations and brain MRI findings suggested a diagnosis of infection-related inflammatory syndrome. Therefore, a combination of corticosteroids and antifungal therapy was initiated. At follow-up, a complete neurological recovery without any relapse was documented. The repeat brain MRI showed complete resolution of the previous lesions. CONCLUSIONS: This case demonstrated that cryptococcal inflammatory syndromes must be suspected in cases of CM if an otherwise unexplained clinical deterioration is observed after initial recovery. The same can happen even before the primary infection is controlled. Thus, timely identification and prompt treatment is vital to reduce the mortality and disability of CM. The administration of corticosteroids in combination with antifungal therapy is an effective strategy in such cases. Clinical course and treatment process of the patient. Hemiparalysis and aphasia improved after the initiation of antifungal treatment. However, the patient developed impaired consciousness companied by deterioration of brain MRI findings. He was treated with adjunctive glucocorticoid taper therapy consisting of dexamethasone (20 mg/day, intravenously) for 1 week followed by oral prednisone 1 mg/kg/day, tapered based on clinical and radiological response, along with amphotericin B (0.6 mg/kg/day, intravenously), voriconazole (400 mg/day in 2 divided doses, intravenously), and 5-flucytosine (100 mg/kg/day in 4 divided doses, orally). Two weeks later, his symptoms improved significantly. After discharge, he began oral voriconazole for consolidation and maintenance therapy for 8 weeks and 9 months respectively. He recovered without any neurological sequelae at 6-month follow-up. Note: MRI = magnetic resonance imaging.

Can the WHO 's recommendations of physical activity volume decrease the risk of heart disease in middle and older aged Chinese People: the evidence from a seven year longitudinal survey.

BACKGROUND: At present, there is a lack of direct evidence to confirm whether the recommendations of the World Health Organization can play a role in fitness and disease prevention in the Chinese population. Therefore, we aimed to analyse 7-year longitudinal survey data to explore whether the physical activity volume recommended by the World Health Organization can help Chinese middle-aged and elderly people reduce the risk of heart disease. METHODS: Data for the 8327 participants who were finally included in this study were derived from the 7-year data of the China Health and Retirement Longitudinal Study (CHARLS) from 2011 to 2018. The physical activity volume is expressed by the product of physical frequency and duration, and heart disease is screened according to self-reported diagnosis and related treatment. The relationship between different physical activity volume groups and the incidence rate of heart disease was determined by a multivariate Cox proportional hazards regression model. RESULTS: After adjusting for all covariates, participants meeting the WHO's recommendations had a 20% lower risk of heart disease than those who did not meet the WHO's recommendations (HR = 0.80, 95% = 0.68-0.96). Subgroup analysis showed that among the participants meeting the WHO's recommendations, men (HR = 0.71) had a lower risk of heart disease than women (HR = 0.74); in addition, the risk of heart disease was significantly reduced in participants who were middle-aged (26%), had a normal BMI range (49%), did not have hypertension (24%), did not have hyperlipidaemia (21%) and did not have lung disease (21%). It should be noted that the risk of heart disease was reduced by 72 and 67% in participants with untreated hyperlipidaemia and untreated lung disease, respectively. CONCLUSIONS: This study revealed that meeting the WHO's recommendations for physical activity volume can reduce the risk of heart disease in middle-aged and older people in China and can also effectively prevent heart disease for people with some common chronic diseases, such as hyperlipidaemia and lung disease. The results showed that physical activity for leisure and exercise had a lower preventive effect on heart disease than physical activity for a job, which may be related to the inappropriate leisure and exercise methods of the participants. TRIAL REGISTRATION: IRB00001052-11015.

Comparison of features and outcomes between HIV-negative patients with Cryptococcus gattii meningitis and Cryptococcus neoformans meningitis in South China.

OBJECTIVES: The objective of this study is to compare the epidemiologic, clinical, laboratory, and imaging features, and outcomes in patients with Cryptococcus gattii meningitis (CGM) and Cryptococcus neoformans meningitis (CNM). METHODS: We performed a retrospective study of HIV-negative patients with CGM and CNM (2015-2021) distinguished by metagenomic next-generation sequencing in cerebrospinal fluid in South China. RESULTS: A total of 81 patients (17 CGM, 64 CNM) were enrolled (72.8% male, median age 49 years, range 21-77 years), and CGM patients were younger (median, 43 vs 53 years, p = .005). Of 17 CGM, VGI and VGII accounted for 70.6% and 29.4%, respectively. CGM patients had less underlying diseases (7/17 [41.2%] vs 48/64 [75%], p = .018) and focal neurologic deficit (3/17 [17.6%] vs 35/64 [54.7%], p = .022), had higher intracranial pressure (15/17 [88.2%] vs 25/64 [39.1%], p = .002), more meningeal enhancement (14/17 [82.4%] vs 32/64 [50%], p = .034), less parenchymal involvement (median, 1 vs 3, p = .018), more lung cryptococcomas (6/12 [50%] vs 6/47 [12.8%], p = .014), faster CSF fungal clearance (p = .004), less complications (median, 1 vs 3, p < .001), and more favourable outcomes (16/17 [94.1%] vs 41/64 [64.1%], p = .035). CONCLUSIONS: This study demonstrated that species identification helps to guide therapy and predict outcomes.

Dinuclear gold catalysis.

Gold chemistry has developed extensively in the past decade, and a dozen good reviews have been presented discussing this progress. Few however have paid close attention to the progress in organic synthesis of dinuclear gold-catalysis. A dinuclear gold catalyst is defined here as a gold complex with two gold centers linked by a bidentate ligand. With theoretical analysis and some representative studies in recent years, this comprehensive review highlights the particular properties of dinuclear gold-complexes, especially aurophilic interactions, and systematically summarizes the recent achievements of dinuclear gold-catalyzed coupling reactions, asymmetric catalysis, and photocatalysis, where dinuclear gold catalysts tend to show a greater advantage than the mononuclear gold catalysts.

Transcription factor GlbHLH regulates hyphal growth, stress resistance, and polysaccharide biosynthesis in Ganoderma lucidum.

Basic helix-loop-helix (bHLH) transcription factors (TFs) participate in many physiological and cellular processes in eukaryotes. However, their functions remain unclear in the macro basidiomycete Ganoderma lucidum (G. lucidum). In this study, a gene encoding bHLH TF, GlbHLH, was identified in G. lucidum. The knockdown of GlbHLH by RNA interference reduced hyphal growth, hyphal branching, and resistant to osmotic, oxidative, and cell wall stress. The content of cell wall components ß-1,3 glucan and chitin and the expression of their synthesis genes were decreased in the GlbHLH knockdown strains. The knockdown of GlbHLH led to an increase of intracellular reactive oxygen species by decreasing the enzyme activity and gene expression of antioxidant enzymes. Furthermore, the production of intracellular polysaccharides and extracellular polysaccharides was greatly decreased in the GlbHLH mutants. These results suggested that GlbHLH is involved in hyphal growth, stress response, and polysaccharide biosynthesis in G. lucidum.