Expression and Characterization of a Novel Cold-Adapted Chitosanase from Marine Renibacterium sp. Suitable for Chitooligosaccharides Preparation

(1) Background: Chitooligosaccharides (COS) have numerous applications due to their excellent properties. Chitosan hydrolysis using chitosanases has been proposed as an advisable method for COS preparation. Although many chitosanases from various sources have been identified, the cold-adapted ones with high stability are still rather rare but required. (2) Methods: A novel chitosanase named CsnY from marine bacterium Renibacterium sp. Y82 was expressed in Escherichia coli, following sequence analysis. Then, the characterizations of recombinant CsnY purified through Ni-NTA affinity chromatography were conducted, including effects of pH and temperature, effects of metal ions and chemicals, and final product analysis. (3) Results: The GH46 family chitosanase CsnY possessed promising thermostability at broad temperature range (0-50 °C), and with optimal activity at 40 °C and pH 6.0, especially showing relatively high activity (over 80% of its maximum activity) at low temperatures (20-30 °C), which demonstrated the cold-adapted property. Common metal ions or chemicals had no obvious effect on CsnY except Mn2+ and Co2+. Finally, CsnY was determined to be an endo-type chitosanase generating chitodisaccharides and -trisaccharides as main products, whose total concentration reached 56.74 mM within 2 h against 2% (w/v) initial chitosan substrate. (4) Conclusions: The results suggest the cold-adapted CsnY with favorable stability has desirable potential for the industrial production of COS.

[Potential pleiotropism of cancer-related single nucleotide polymorphisms among Chinese population]

Objective: To investigate the potential pleiotropism of cancer-related single nucleotide polymorphisms (SNPs) among Chinese population. Methods: Based on the catalogue of GWAS jointly constructed by the National Human Genome Research Institute and the European Institute of Bioinformatics, according to population origin (Chinese population and non-Chinese population) and disease traits (cancer and non-cancer traits). All SNPs found by GWAS before August 2020 were divided into four categories: cancer in Chinese population, non-cancer in Chinese population, cancer in non-Chinese population and non-cancer in non-Chinese population. The number, correlation and linkage of the four categories of SNPs were described. Results: By August 2020, a total of 196 813 SNPs from 4 096 GWAS were included in the GWAS directory. The information that SNPs refer to unknown or were not related to the disease was excluded, and 117 441 independent SNPs were finally included. There were 619 SNPs related to cancer and 9 569 SNPs related to non-cancer disease in Chinese population, respectively. There were 4 624 SNPs related to cancer and 106 448 SNPs related to non-cancer disease (trait) in non-Chinese population, respectively. Three SNPs, rs2736100, rs6983267 and rs401681, were associated with two or more types of cancer in both Chinese and non-Chinese populations. Seven SNPs, rs7705526, rs2736100, rs10993994, rs2735839, rs4430796, rs174537 and rs9271588, were associated with cancer and non-cancer diseases in both Chinese and non-Chinese populations, respectively. Conclusion: There is a potential pleiotropism of cancer-related SNPs in Chinese population.

Whole conversion of agro-industrial wastes rich in galactose-based carbohydrates into lipid using oleaginous yeast Aureobasidium namibiae

BACKGROUND

Raw materials composed of easily assimilated monosaccharides have been employed as carbon source for production of microbial lipids. Nevertheless, agro-industrial wastes rich in galactose-based carbohydrates have not been introduced as feedstocks for oleaginous yeasts.

RESULTS

In this study, Aureobasidium namibiae A12 was found to efficiently accumulate lipid from soy molasses and whey powder containing galactose-based carbohydrates, with lipid productions of 5.30 g/L and 5.23 g/L, respectively. Over 80% of the fatty acids was C_16:0, C_18:0, C_18:1, and C_18:2. All kinds of single sugar components in the two byproducts were readily converted into lipids, with yields ranging between 0.116 g/g and 0.138 g/g. Three α-galactosidases and five β-galactosidases in the strain were cloned and analyzed. Changes of transcriptional levels indicated GalB and GalC were key α-galactosidases, and GalG was key β-galactosidase. In 10 L fermentor, lipid production from SM and WP achieved 6.45 g/L and 6.13 g/L, respectively. β-galactosidase was responsible for lactose hydrolysis; sucrase and α-galactosidase both contributed to the efficient hydrolysis of raffinose and stachyose in a cooperation manner.

CONCLUSIONS

This is a new way to produce lipids from raw materials containing galactose-based carbohydrates. This finding revealed the significance of sucrase in the direct hydrolysis of galactose-based carbohydrates in raw materials for the first time and facilitated the understanding of the efficient utilization of galactose-based carbohydrates to manufacture lipid or other chemicals in bioprocess.

A Comparative Insight on the Newly Emerging Rifamycins: Rifametane, Rifalazil, TNP-2092 and TNP-2198

Rifamycins are considered a milestone for tuberculosis (TB) treatment because of their proficient sterilizing ability. Currently, available TB treatments are complicated and need a long duration, which ultimately leads to failure of patient compliance. Some new rifamycin derivatives, i.e., rifametane, TNP-2092 (rifamycin-quinolizinonehybrid), and TNP-2198 (rifamycin-nitromidazole hybrid) are under clinical trials, which are attempting to overcome the problems associated with TB treatment. The undertaken review is intended to compare the pharmacokinetics, pharmacodynamics and safety profiles of these rifamycins, including rifalazil, another derivative terminated in phase II trials, and already approved rifamycins. The emerging resistance of microbes is an imperative consideration associated with antibiotics. Resistance development potential of microbial strains against rifamycins and an overview of chemistry, as well as structure-activity relationship (SAR) of rifamycins, are briefly described. Moreover, issues associated with rifamycins are discussed as well. We expect that newly emerging rifamycins shall appear as potential tools for TB treatment in the near future.

Intraductal carcinoma of the prostate in prostate biopsy samples: correlation with aggressive pathological features after radical prostatectomy and prognostic value in high-risk prostate cancer

Intraductal carcinoma of the prostate (IDC-P) is an aggressive pathological pattern of prostate cancer (PCa). We investigated the association of IDC-P in prostate biopsy (PBx) with several pathological features after radical prostatectomy (RP) and its prognostic value in high-risk PCa. A total of 418 patients with high-risk PCa after RP were included in this study. IDC-P and its architectural patterns were identified according to the 2016 World Health Organization Classification. Chi-squared test and logistic regression were used to investigate the correlation between IDC-P and post-RP pathological features. Kaplan–Meier curves and Cox regression were applied to explore the prognostic value of IDC-P. IDC-P was identified in PBx in 36/418 (8.6%) patients. Logistic regression indicated that IDC-P in PBx was independently associated with several pathological features of RP, including Gleason score 8–10 (P < 0.001), seminal vesicular invasion (P < 0.001), and pathological T (pT) 3a (P = 0.043). Patients with IDC-P in PBx manifested poorer biochemical-free survival (BFS) than those without IDC-P (37.47 months vs not reached, P < 0.001). The addition of IDC-P in several prognostic nomograms could improve the predictive accuracy of these tools. We conclude that IDC-P in PBx is positively associated with several aggressive pathological features after RP in high-risk PCa. In addition, IDC-P in PBx could effectively predict the BFS of high-risk PCa patients after RP.

Ex Vivo Liver Resection and Autotransplantation as Surgical Option for Zone II-III Leiomyosarcoma of IVC: A Case Report and Literature Review

We report the first documented case of leiomyosarcoma at zone II-III of inferior vena cava with thrombi in three hepatic veins undergoing ex vivo liver resection and autotransplantation (ELRA) and hepatic veins thrombectomy. A 33-year-old female patient presented with abdominal distention and lower extremities edema. Abdominal wall varicosis and shifting dullness were positive on physical examination. Her liver function was classified as Child-Pugh B and a solid tumor at retro-hepatic vena cava extending to right atrium with thrombi in three hepatic veins were confirmed. The diagnosis of leiomyosarcoma with Budd-Chiari syndrome was highly suspected with preoperative ultrasound, echocardiogram, CT scan, and three-dimensional reconstruction. A zone II-III leiomyosarcoma of IVC origin was confirmed at surgery and ex vivo liver resection and autotransplantation, and hepatic vein thrombectomy with atrial reconstruction were performed under cardiopulmonary bypass (CPB). Operative time, anhepatic time, and CPB time were 12 h, 128 min, and 84 min, respectively. The patients experienced post-operative liver dysfunction and was cured with conservative therapy. Hepatic recurrence two years after surgery was managed with radiofrequency. The patient was alive with liver metastasis three years after surgery. Despite being regarded as an extremely aggressive procedure, ELRA could be considered in the treatment of advanced leiomyosarcoma with Budd-Chiari syndrome and hepatic vein thrombi.

Analysis of selection signatures on the Z chromosome of bidirectional selection broiler lines for the assessment of abdominal fat content

Background

The discovery of selection signatures has enabled the identification of genomics regions under selective pressure, enhancing knowledge of evolutionary genotype-phenotypes. Sex chromosomes play an important role in species formation and evolution. Therefore, the exploration of selection signatures on sex chromosomes has important biological significance.

Results

In this study, we used the Cross Population Extend Haplotype Homozygosity Test (XPEHH), F-statistics (F_ST) and EigenGWAS to assess selection signatures on the Z chromosome in 474 broiler chickens via Illumina chicken 60 K SNP chips. SNP genotype data were downloaded from publicly available resources. We identified 17 selection regions, amongst which 1, 11 and 12 were identified by XPEHH, F_ST, and EigenGWAS, respectively. Each end of the Z chromosome appeared to undergo the highest levels of selection pressure. A total of 215 candidate genes were located in 17 selection regions, some of which mediated lipogenesis, fatty acid production, fat metabolism, and fat decomposition, including FGF10, ELOVL7, and IL6ST. Using abdominal adipose tissue expression data of the chickens, 187 candidate genes were expressed with 15 differentially expressed genes (DEGs) in fat vs. lean lines identified. Amongst the DEGs, VCAN was related to fat metabolism. GO pathway enrichment analysis and QTL annotations were performed to fully characterize the selection mechanism(s) of chicken abdominal fat content.

Conclusions

We have found some selection regions and candidate genes involving in fat metabolism on the Z chromosome. These findings enhance our understanding of sex chromosome selection signatures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12863-021-00971-6.

Nonlinear microfluidics: device physics, functions, and applications

The microfluidic flow is typically laminar due to the dominant viscous effects. At Reynolds numbers far below 1 (Re ≪ 1), the fluid inertia can be neglected. For the steady flow of incompressible Newtonian fluids, it approaches linear Stokes flow. At intermediate Re, there exists a weak-inertia flow regime where secondary flows such as Dean vortices are accessible for microfluidic manipulations. Apart from the fluid inertia, other nonlinear factors such as the non-Newtonian fluid properties, concurrent flow of dissimilar fluids, compliant fluidic structures and stimuli-responsive materials can also cause intriguing flow behaviours. Through proper designs, they can be applied for a variety of microfluidic components including mixers, valves, oscillators, stabilizers and auto-regulators etc., greatly enriching the microfluidic flow control and manipulation strategies. Due to its unique working characteristics and advantages, nonlinear microfluidics has increasingly attracted extensive attention. This review presents a systematic survey on this subject. The designs of typical nonlinear microfluidic devices, their working mechanisms, key applications, and the perspective of their future developments will be discussed. The nonlinear microfluidic techniques are believed to play an essential role in the next generation of highly-integrated, automated, and intelligent microfluidics.

[An analysis of the status quo of ground-level ozone pollution research]

Objective: To analyze the research status of ground-level ozone pollution, explore research trends and hot spots, and provide references for future research on air pollution. Methods: Papers on ground-level ozone pollution research published before December 31, 2019 had been retrieved in SCI-E database of the "Web of Science Core Collection" in January 2020. The retrieval strategies were set as follows: TS= ( ("Tropospheric Ozone" OR "Low Level Ozone" OR "Ground Level Ozone") AND ("Air pollution*" OR "Air quality") ) . The survey included 2084 articles. By using bibliometric research and visual analysis tools, the research status of global ground-level ozone pollution was revealed from the aspects of time, discipline, journal, financing, institution, country and key words. Results: Cumulative publications increased in a cubic function of y=0.05x(3)+0.80x(2)+0.74x+4.55 (R(2)=0.999, P<0.01) . The most studied subject was Environmental sciences ecology (1401 articles, 67.23%) . Atmospheric Environment was the journal with the most articles (332 articles, 15.93%) . The United States was the country with the most publications (44.67%, 931/2084) , while China ranked second (17.13%, 357/2084) . 80.39% (287/357) of Chinese papers had funding information. Among the top 10 research institutions, 7 and 2 were affiliated to the United States and China respectively. Source apportionment and human health were high frequency keywords that had appeared in the last 5 years. Conclusion: The research on ground-level ozone pollution is in a good period of development. The United States has a leading position in this area, and China has a good prospect in this field. Pollution source apportionment and human health effects are new research directions.

[Analysis of distribution characteristics and influencing factors of healthy and long-lived people in Shanglin area of Nanning, Guangxi Zhuang Autonomous Region]

Objective: To explore the epidemiologic characteristics of long-lived population and influencing factors in Shanglin county of Guangxi and provide scientific basis for the study of health and longevity in Guangxi. Methods: We collected and analyzed the general demographic cross-sectional data of the long-lived individuals (≥90 years old) in 11 villages and towns by multi-source registration and face-to-face interview. The age group control design was adopted to conduct a comparison among the longevity group (90-100 years old), centenarian group (≥100 years old), the longevity plus centenarian group and control group (local population aged 40-85 years), and identify the factors related to longevity. Results: Among the 496 007 people registered in Shanglin, 1 533 were aged ≥90 years, including 1 453 in the longevity group, with an average age of (92.84±2.46) years, and 80 in the centenarian group, with an average age of (102.67±2.60) years. The spatial distribution of long-lived individuals and centenarians was mainly in the north and central areas, and sparse in southwest area. Analysis on factors related to health and longevity indicated that old people with Zhuang ethnic (OR=1.551,95%CI:1.308-1.838), married (OR=55.507,95%CI:36.087-85.377) and moderately high waist-to-hip ratio (OR=258.056,95%CI:27.775-2 397.569), and SBP (OR=1.019,95%CI:1.013-1.026) tended to live longer. Conclusions: We found that the rate of longevity in Shanglin was higher than the average level in Guangxi and China. Longevity in Shanglin country had unique spatial and population distribution characterics of female longevity more than male longevity, mainly Zhuang ethnic and so on. Being women, married, family history of longevity, appropriate high waist-to-hip ratio, SBP and blood sugar level might be positive factors for longevity in Shanglin, but the impacts of other factors on longevity need further study.

[The study on the distribution characteristics and relevant factors of healthy and long-lived people in multiple regions of Guangxi Zhuang Autonomous Region]

Objective: To investigate the epidemiological characteristics and relevant factors among individuals characterized by their longevity in multiple regions of Guangxi Zhuang Autonomous Region, and provide a valuable scientific perspective for the research in health and longevity of the elderly in Guangxi. Methods: Registration and face-to-face questionnaire on a door-to-door basis were adopted to collect the demographic characteristics of the long-lived individuals (≥90 years old) in Bama of Hechi city, Yongfu of Guilin city, Dongxing of Fangchenggang city, Guangxi. Then, among the local general population, individuals within the age group between 40 and 85 years old were selected randomly as controls. Correlations were then analyzed between the relative health and longevity of the subjects and their gender, ethnicity, family history, disease history, marital status, the number of family generations, the number of children, smoking, drinking, outdoor activities, sleep and other health-related factors, then the result was subject to further analysis by comparing the long-lived population and the control population respectively. Results: Among 691 500 of the permanent residents of Bama, Yongfu and Dongxing city, 1 005 cases were 90 years old and over with a ratio of 145.34 out of 100 000 persons; within the 1 005 cases, 944 were aged between 90 and 100 (longevity rate: 136.51/100 000) with an average age of (93.28±2.57); 61 cases were aged 100 or over, arriving at a centenarian rate of 8.82/100 000 with an average age of (102.00±3.05) years. Significant differences were found just among three particular factors - regional distribution (P=0.014), history of disease (P=0.002), four generations of family (P=0.008) between nonagenarians and centenarians (P<0.05), while the other 15 indicators did not show anything noteworthy. The result indicated that longevity and centenarians might be the same group and then we combined both groups into one. By cross-comparison between the longevity-plus- centenarians and the control group in the region, factors listed below exhibited significant correlation with health and longevity: marital status (OR=26.469, 95%CI: 13.208-53.045), number of generations within the family (OR=5.419, 95%CI: 3.418-8.592), number of male offspring (OR=2.013, 95%CI: 1.555-2.607), number of female offspring (OR=1.380, 95%CI: 1.122-1.696), and the frequency of outdoor activities (OR=10.226, 95%CI: 3.164-33.045). Conclusions: The longevity rate is higher in the general natural population in Bama, Yongfu and Dongxing of Guangxi. The phenomenon may owe to favorable family structure, atmosphere within or out of the family or other elements related with social surrounding. Among them all, mentality, inclination to physical exercise and regular rhythm of life may all exert tremendous contributory influence here.

Pyrimidazole-Based Covalent Organic Frameworks: Integrating Functionality and Ultrastability via Isocyanide Chemistry

Development of new chemistry to simultaneously meet the demands for topology, connectivity, and functionality is highly desired in the research area of covalent organic frameworks (COFs). We explore herein the isocyanide chemistry so as to establish a facile paradigm to integrate functionality and ultrastability in COFs. Using the representative Groebke-Blackburn-Bienaymé (GBB) reaction based on isocyanide chemistry, we are able to construct a series of pyrimidazole-based COFs in one step from isocyanide, aminopyridine, and aldehyde monomers. Diversified functionalities have been bottom-up integrated by the simple replacement of readily available 2-aminopyridine monomers. Meanwhile, the ubiquitous formation of fused imidazole rings within the frameworks has guaranteed their ultrastability. In view of the rich synthetic possibilities provided by isocyanide chemistry, we expect that this contribution opens up a new avenue toward the divergent construction of robust COFs for practical applications.

Bench-stable imine surrogates for the one-pot and catalytic asymmetric synthesis of α-amino esters/ketones

N,O-Bis(tert-butoxycarbonyl)hydroxylamines are readily accessible as imine surrogates, which are bench stable and could quantitatively generate the corresponding imines for in situ applications. An unpresented catalytic asymmetric method for the synthesis of α-amino esters and ketones from novel imine surrogates, N,O-bis(tert-butoxycarbonyl)hydroxylamines, as well as its preliminary mechanistic studies are reported. A variety of optically enriched products were obtained in excellent yields and enantioselectivities (up to 99% yield and >99% ee).

[Therapeutic efficacy analysis of immunotherapy in small cell lung cancer]

Objective: Recently, increasing number of lung cancer patients benefit from immune-checkpoint inhibitors (ICIs). However, the data of Chinese small cell lung cancer (SCLC) patients is limited. This study aims to analyze the response and survival data of ICIs treatment in SCLC and to explore the predictive biomarkers. Methods: Forty-seven SCLC patients who received ICIs treatment from Peking University Cancer Hospital from May 2017 to September 2019 was recruited. Clinical characteristics including sex, age, smoking status, ICIs strategy, PD-L1 expression and therapeutic efficacy were collected to explore the clinical predictive biomarkers for SCLC ICIs treatment. Results: Among the 47 patients, 18 (38.3%) cases were partial repose (PR), 11 (23.4%) were stable disease (SD), 18 (38.3%) were progressive disease (PD), and the objective response rate (ORR) was 38.3%, disease control rate (DCR) was 61.7%, the median progression-free survival (PFS) was 5.3 months. ICIs monotherapy accounts for 27.7%, the ORR was 15.4%, DCR was 53.8%, median PFS was 2.7 months. Combined therapy accounts for 72.3%, the ORR was 47.1%, DCR was 64.7%, median PFS was 5.4 months. Fourteen (29.8%) patients received ICIs as the first line treatment, their ORR was 85.7%, DCR was 100%, median PFS was 9.1 month. The ORR was not related to the age, sex, body mass index (BMI), smoking status and programmed death-ligand 1 (PD-L1) expression (P>0.05). The ORRs were higher in patients underwent PD-L1 monotherapy (P=0.001), combined therapy (P=0.002) and received ICIs as the first line treatment (P<0.001). Log-rank analysis indicated that the PFS of female patients were 12.0 months, significantly longer than 4.4 months of male patients in ICIs treatment (P=0.038). Patients who received PD-L1 monotherapy, combined treatment, or ICIs as the first line treatment had longer PFS than their counterparts, though no statistical significant was observed (P>0.05). Cox multivariate analysis showed that, the gender was not an independent predictor for PFS in ICIs treatment (HR=3.777, 95%CI=0.974~30.891, P=0.054). Conclusions: Immunotherapy is an effective treatment strategy for SCLC. Patients who receive combined ICIs treatment, first line ICIs treatment and PD-L1 treatment may get greater benefits. PD-L1 expression cannot predict the response and PFS in SCLC ICIs treatment.

Production of a thermo-tolerant κ-carrageenase via a food-grade host and anti-oxidant activity of its enzymatic hydrolysate

κ-Carrageenase cleaves the β-(1-4) linkages of κ-carrageenan into κ-carrageenan oligosaccharides (κ-COS), which exhibit various biological activities. In this study, a glycoside hydrolase (GH) family 16 κ-carrageenase gene, cgkA, was cloned from the marine bacterium Vibrio sp. SY01 and secretory expressed in a food-grade host, Yarrowia lipolytica. The specific activity of the purified CgkA was 12.5 U/mg. Determination of biochemical properties showed that CgkA was a thermo-tolerant enzyme, and 59.9% of the initial enzyme activity was recovered by immediately placing the sample at 20 °C for 30 min after enzymatic inactivation by boiling for 5 min. The recombinant CgkA was an endo-type enzyme, the main enzymatic product was κ-carradiaose (accounting for 87.6% of total products), and κ-carratetraose was the minimum substrate. Additionally, in vitro and in vivo analyses indicated that enzymatic κ-carradiaose possesses anti-oxidant activity. These features make CgkA as a promising candidate for biotechnological applications in the production of anti-oxidant κ-COS.

Non-Interpenetrated Single-Crystal Covalent Organic Frameworks

Growth of covalent organic frameworks (COFs) as single crystals is extremely challenging. Inaccessibility of open-structured single-crystal COFs prevents the exploration of structure-oriented applications. Herein we report for the first time a non-interpenetrated single-crystal COF, LZU-306, which possesses the open structure constructed exclusively via covalent assembly. With a high void volume of 80 %, LZU-306 was applied to investigate the intrinsic dynamics of reticulated tetraphenylethylene (TPE) as the individual aggregation-induced-emission moiety. Solid-state ² H NMR investigation has determined that the rotation of benzene rings in TPE, being the freest among the reported cases, is as fast as 1.0×10⁴  Hz at 203 K to 1.5×10⁷  Hz at 293 K. This research not only explores a new paradigm for single-crystal growth of open frameworks, but also provides a unique matrix-isolation platform to reticulate functional moieties into a well-defined and isolated state.

Synthesis of Vitamin B12-Antibiotic Conjugates with Greatly Improved Activity against Gram-Negative Bacteria

There is an urgent need to discover new antibiotics and improve the efficacy of known antibiotics against Gram-negative bacteria. "Trojan horse" conjugates are novel and promising antibiotics. Herein we report the design and synthesis of vitamin-B₁₂-ampicillin conjugates, which exhibited more than 500 times improved activity against Escherichia coli compared with ampicillin itself. Our studies demonstrate that the vitamin-B₁₂ uptake pathway could be employed for effective antibiotic delivery and efficacy enhancement.

Characterization of Nuclear and Mitochondrial Genomes of Two Tobacco Endophytic Fungi Leptosphaerulina chartarum and Curvularia trifolii and Their Contributions to Phylogenetic Implications in the Pleosporales

The symbiont endophytic fungi in tobacco are highly diverse and difficult to classify. Here, we sequenced the genomes of Curvularia trifolii and Leptosphaerulina chartarum isolated from tobacco plants. Finally, 41.68 Mb and 37.95 Mb nuclear genomes were sequenced for C. trifolii and L. chartarum with the scaffold N50, accounting for 638.94 Kb and 284.12 Kb, respectively. Meanwhile, we obtained 68,926 bp and 59,100 bp for their mitochondrial genomes. To more accurately classify C. trifolii and L. chartarum, we extracted seven nuclear genes and 12 mitochondrial genes from these two genomes and their closely related species. The genes were then used for calculation of evolutionary rates and for phylogenetic analysis. Results showed that it was difficult to achieve consistent results using a single gene due to their different evolutionary rates, while the phylogenetic trees obtained by combining datasets showed stable topologies. It is, therefore, more accurate to construct phylogenetic relationships for endophytic fungi based on multi-gene datasets. This study provides new insights into the distribution and characteristics of endophytic fungi in tobacco.

Cloning, Secretory Expression and Characterization of a Unique pH-Stable and Cold-Adapted Alginate Lyase

Cold-adapted alginate lyases have unique advantages for alginate oligosaccharide (AOS) preparation and brown seaweed processing. Robust and cold-adapted alginate lyases are urgently needed for industrial applications. In this study, a cold-adapted alginate lyase-producing strain Vibrio sp. W2 was screened. Then, the gene ALYW201 was cloned from Vibrio sp. W2 and expressed in a food-grade host, Yarrowia lipolytica. The secreted Alyw201 showed the activity of 64.2 U/mL, with a molecular weight of approximate 38.0 kDa, and a specific activity of 876.4 U/mg. Alyw201 performed the highest activity at 30 °C, and more than 80% activity at 25-40 °C. Furthermore, more than 70% of the activity was obtained in a broad pH range of 5.0-10.0. Alyw201 was also NaCl-independent and salt-tolerant. The degraded product was that of the oligosaccharides of DP (Degree of polymerization) 2-6. Due to its robustness and its unique pH-stable property, Alyw201 can be an efficient tool for industrial production.

High-solubility aromatic polyesters with fluorene and phthalein groups: Synthesis and property

A series of aromatic polyesters bearing fluorene and phthalein groups were synthesized from commercially available 9,9-bis(4-hydroxyphenyl)fluorene (BPF), phenolphthalein, and terephthaloyl chloride through an interfacial polymerization method. The microstructure, molecular weight, morphology, thermal properties, and thermal decomposition mechanism of these aromatic polyesters were investigated. Their mechanical properties were also evaluated. The results suggested that the copolymer compositions were approximately equal to the feed compositions. Moreover, the increase in the BPF unit content increased the glass transition and weight loss temperatures of the aromatic polyesters, owing to the strong rigidity of the bulky fluorene group. All the polymers were amorphous and exhibited good solubility in common organic solvents. Hence, the synthesized polymers could be easily cast into flexible films. The copolymer film samples exhibited better mechanical properties than those of the homopolymers. The tensile strength, Young’s modulus, and elongation at break of the polymers first increased gradually, and then decreased with increasing BPF content. Notably, the copolymers exhibited the best mechanical properties at the BPF content range 30–50%. Owing to their characteristics, these synthesized polymers show great potential for application as high performance membrane materials.

Biglycan as a potential diagnostic and prognostic biomarker in multiple human cancers

Biglycan (BGN), a key member of the small leucine-rich proteoglycan family, is an important component of the extracellular matrix. Clinical studies have demonstrated that upregulation of BGN is associated with poor prognosis in patients with various types of solid cancer. The present study analyzed the mRNA expression levels of BGN in various types of solid cancer when compared with that in normal tissues via the Oncomine database. The UALCAN, OncoLnc and Kaplan-Meier Plotter databases were additionally used to evaluate the prognostic values of BGN in patients with solid cancer and co-expression gene analysis was conducted using the protein-protein interaction networks of BGN. The present study observed that the mRNA expression levels of BGN were increased in bladder, brain and central nervous system, breast, colorectal, esophageal, gastric, head and neck, lung, ovarian and 28 subtypes of cancer compared with normal tissues. The increased expression of BGN was identified to be associated with a poor outcome in ovarian and gastric cancer. Based on the co-expression network, BGN was identified as the key gene in a 43-gene network. The present findings of increased expression of BGN in solid tumors and its positive association with poor outcome on patient survival indicate that BGN may serve as a prognostic marker and as a target for novel therapeutics for multiple types of cancer.