The Role of the Residue at Position 2 in the Catalytic Activity of AA9 Lytic Polysaccharide Monooxygenases.

AA9 lytic polysaccharide monooxygenases (LPMOs) are copper-dependent metalloenzymes that play a major role in cellulose degradation and plant infection. Understanding the AA9 LPMO mechanism would facilitate the improvement of plant pathogen control and the industrial application of LPMOs. Herein, via point mutation, we investigated the role of glycine 2 residue in cellulose degradation by Thermoascus aurantiacus AA9 LPMOs (TaAA9). A computational simulation showed that increasing the steric properties of this residue by replacing glycine with threonine or tyrosine altered the H-bonding network of the copper center and copper coordination geometry, decreased the surface charge of the catalytic center, weakened the TaAA9-substrate interaction, and enhanced TaAA9-product binding. Compared with wild-type TaAA9, G2T-TaAA9 and G2Y-TaAA9 variants showed attenuated copper affinity, reduced oxidative product diversity and decreased substrate Avicel binding, as determined using ITC, MALDI-TOF/TOF MS and cellulose binding analyses, respectively. Consistently, the enzymatic activity and synergy with cellulase of the G2T-TaAA9 and G2Y-TaAA9 variants were lower than those of TaAA9. Hence, the investigated residue crucially affects the catalytic activity of AA9 LPMOs, and we propose that the electropositivity of copper may correlate with AA9 LPMO activity. Thus, the relationship among the amino acid at position 2, surface charge and catalytic activity may facilitate an understanding of the proteins in AA9 LPMOs.

Identification of a thermostable fungal lytic polysaccharide monooxygenase and evaluation of its effect on lignocellulosic degradation.

Auxiliary activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) show significant synergism with cellulase in cellulose degradation. In recent years, there have been many reports on AA9 LPMOs; however, the identification of efficient and thermostable AA9 LPMOs with broad potential for industrial applications remains necessary. In this study, a new AA9 LPMO from Talaromyces cellulolyticus, named TcAA9A, was identified. An analysis of the oxidation products of phosphoric acid-swollen cellulose categorized TcAA9A as a type 3 AA9 LPMO, and TcAA9A exhibited a better synergistic effect with cellulase from Trichoderma reesei than what is seen with TaAA9A, a well-studied AA9 LPMO from Thermoascus aurantiacus. Two AA9 LPMOs were successfully expressed in T. reesei, and the transformants were named TrTcAA9A and TrTaAA9A. The activities and thermostabilities of the AA9 LPMOs in TrTcAA9A were higher than those of the AA9 LPMOs in TrTaAA9A or the parent. The enzyme solution of TrTcAA9A was more efficient than that of the parent or TrTaAA9A for the degradation of Avicel and delignified corncob residue. Thus, TcAA9A showed a better performance than TaAA9A in T. reesei cellulase cocktails. This study may offer an innovative solution for improving enzyme cocktail activity for lignocellulosic degradation.

Synergistic and Dose-Controlled Regulation of Cellulase Gene Expression in Penicillium oxalicum.

Filamentous fungus Penicillium oxalicum produces diverse lignocellulolytic enzymes, which are regulated by the combinations of many transcription factors. Here, a single-gene disruptant library for 470 transcription factors was constructed and systematically screened for cellulase production. Twenty transcription factors (including ClrB, CreA, XlnR, Ace1, AmyR, and 15 unknown proteins) were identified to play putative roles in the activation or repression of cellulase synthesis. Most of these regulators have not been characterized in any fungi before. We identified the ClrB, CreA, XlnR, and AmyR transcription factors as critical dose-dependent regulators of cellulase expression, the core regulons of which were identified by analyzing several transcriptomes and/or secretomes. Synergistic and additive modes of combinatorial control of each cellulase gene by these regulatory factors were achieved, and cellulase expression was fine-tuned in a proper and controlled manner. With one of these targets, the expression of the major intracellular ß-glucosidase Bgl2 was found to be dependent on ClrB. The Bgl2-deficient background resulted in a substantial gene activation by ClrB and proved to be closely correlated with the relief of repression mediated by CreA and AmyR during cellulase induction. Our results also signify that probing the synergistic and dose-controlled regulation mechanisms of cellulolytic regulators and using it for reconstruction of expression regulation network (RERN) may be a promising strategy for cellulolytic fungi to develop enzyme hyper-producers. Based on our data, ClrB was identified as focal point for the synergistic activation regulation of cellulase expression by integrating cellulolytic regulators and their target genes, which refined our understanding of transcriptional-regulatory network as a "seesaw model" in which the coordinated regulation of cellulolytic genes is established by counteracting activators and repressors.

Regulation of cellulase expression, sporulation, and morphogenesis by velvet family proteins in Trichoderma reesei.

Homologs of the velvet protein family are encoded by the ve1, vel2, and vel3 genes in Trichoderma reesei. To test their regulatory functions, the velvet protein-coding genes were disrupted, generating Δve1, Δvel2, and Δvel3 strains. The phenotypic features of these strains were examined to identify their functions in morphogenesis, sporulation, and cellulase expression. The three velvet-deficient strains produced more hyphal branches, indicating that velvet family proteins participate in the morphogenesis in T. reesei. Deletion of ve1 and vel3 did not affect biomass accumulation, while deletion of vel2 led to a significantly hampered growth when cellulose was used as the sole carbon source in the medium. The deletion of either ve1 or vel2 led to the sharp decrease of sporulation as well as a global downregulation of cellulase-coding genes. In contrast, although the expression of cellulase-coding genes of the ∆vel3 strain was downregulated in the dark, their expression in light condition was unaffected. Sporulation was hampered in the ∆vel3 strain. These results suggest that Ve1 and Vel2 play major roles, whereas Vel3 plays a minor role in sporulation, morphogenesis, and cellulase expression.

Contributing factors in the improvement of cellulosic H2 production in Clostridium thermocellum/Thermoanaerobacterium co-cultures.

Lignocellulosic biohydrogen is a promising renewable energy source that could be a potential alternative to the unsustainable fossil fuel-based energy. Biohydrogen production could be performed by Clostridium thermocellum that is the fastest known cellulose-degrading bacterium. Previous investigations have shown that the co-culture of C. thermocellum JN4 and a non-cellulolytic bacterium Thermoanaerobacterium thermosaccharolyticum GD17 produces more hydrogen than the C. thermocellum JN4 mono-culture, but the mechanism of this improvement is unknown. In this work, we carried out genomic and evolutionary analysis of hydrogenase-coding genes in C. thermocellum and T. thermosaccharolyticum, identifying one Ech-type [NiFe] hydrogenase complex in each species, and, respectively, five and four monomeric or multimeric [FeFe] hydrogenases in the two species. Further transcriptional analysis showed hydrogenase-coding genes in C. thermocellum are regulated by carbon sources, while hydrogenase-coding genes in T. thermosaccharolyticum are not. However, comparison between transcriptional abundance of hydrogenase-coding genes in mono- and co-cultures showed the co-culturing condition leads to transcriptional changes of hydrogenase-coding genes in T. thermosaccharolyticum but not C. thermocellum. Further metabolic analysis showed T. thermosaccharolyticum produces H2 at a rate 4-12-fold higher than C. thermocellum. These findings lead to the suggestion that the improvement of H2 production in the co-culture over mono-culture should be attributed to changes in T. thermosaccharolyticum but not C. thermocellum. Further suggestions can be made that C. thermocellum and T. thermosaccharolyticum perform highly specialized tasks in the co-culture, and optimization of the co-culture for more lignocellulosic biohydrogen production should be focused on the improvement of the non-cellulolytic bacterium.

Balancing mechanical property and swelling behavior of bacterial cellulose film by in-situ adding chitosan oligosaccharide and covalent crosslinking with γ-PGA.

Bacterial cellulose (BC) is an ideal candidate material for drug delivery, but the disbalance between the swelling behavior and mechanical properties limits its application. In this work, covalent crosslinking of γ-polyglutamic acid (γ-PGA) with the chitosan oligosaccharide (COS) embedded in BC was designed to remove the limitation. As a result, the dosage, time, and batch of COS addition significantly affected the mechanical properties and the yield of bacterial cellulose complex film (BCCF). The addition of 2.25 % COS at the incubation time of 0.5, 1.5, and 2 d increased the Young's modulus and the yield by 5.65 and 1.42 times, respectively, but decreased the swelling behavior to 1774 %, 46 % of that of native BC. Covalent γ-PGA transformed the dendritic structure of BCCF into a spider network, decreasing the porosity and increasing the swelling behavior by 3.46 times. The strategy balanced the swelling behavior and mechanical properties through tunning hydrogen bond, electrostatic interaction, and amido bond. The modified BCCF exhibited a desired behavior of benzalkonium chlorides transport, competent for drug delivery. Thereby, the strategy will be a competent candidate to modify BC for such potential applications as wound dressing, artificial skin, scar-inhibiting patch, and so on.

Application and modification of bone cement in vertebroplasty: A literature review.

Vertebral compression fractures are more common in the elderly, particularly in postmenopausal women. Most of these people are accompanied by osteoporosis, which can easily lead to spinal deformities and fractures. Once a fracture occurs, the patient would have severe pain response, limited spinal movement, and need to stay in bed for a long time, resulting in a significant decrease in their quality of life. Percutaneous vertebroplasty (PVP) is a minimally invasive spinal surgery that injects bone cement into the diseased vertebrae for therapeutic purposes. It can quickly relieve pain and stabilize the spine. It is widely used in the treatment of vertebral compression fractures and is currently an ideal treatment method. There are many materials of bone cement used in clinical treatment, and each material has unique characteristics. Many scholars would modify the bone cement according to the advantages and disadvantages to make it more suitable for clinical use. In this review, we discuss the clinical application and modification of bone cement.

Alleviating Nonproductive Adsorption of Lignin on CBM through the Addition of Cationic Additives for Lignocellulosic Hydrolysis.

The nonproductive adsorption of cellulase onto lignin significantly inhibited the enzymatic hydrolysis of lignocellulosic biomass. In this study, we constructed a rapid fluorescence detection (RFD) system, and using this system, we demonstrated that the addition of cationic additives DTAB or polyDADMAC greatly increased the partition coefficients of cellulose/lignin, reduced nonproductive adsorption, and enhanced the hydrolysis efficiency of lignocellulose compared to those of Tweens or PEGs. Moreover, the addition of polyDADMAC and DTAB increased the glucose yield released from the mixture of Avicel and AICS-lignin (MCL) by 16.9 and 20.6%, respectively, and reduced the inhibition rate of lignin by 16.9 and 20.7%, respectively. Interestingly, polyDADMAC or DTAB treatment performed more effectively for the enzymatic hydrolysis of pretreated lignocellulosic biomass, compared with MCL. We confirmed that the reduced hydrophobicity and increased zeta potential of lignin cocontribute to the dampening nonproductive adsorption of lignin. In particular, the zeta potential values of lignin and the partition coefficients of Avicel/lignin with the addition of additives showed a good correlation, suggesting that electrostatic force also plays a crucial role in the adsorbing of cellulase on lignin. This work will be conducive to decreasing the nonproductive binding of cellulase onto lignin and enhancing cellulose conversion.

Preparation and Biocompatibility Evaluation of Nanoscale Isoniazide-Loaded Mineralized Collagen Implants for Tuberculous Bone and Joint Repair.

Bone and joint tuberculosis is an extremely severe infectious disease that commonly occurs due to the primary infection of a type of mycobacteria, called Mycobacterium tuberculosis. Under the current scenario, there are very limited supplies of bone grafts available for the treatment of deceased bone, including autogenous bone and synthetic biomaterials. The present study aimed to construct a nanoscale isoniazid-loaded mineralized collagen implant, and then to explore its physicochemical properties and to investigate its biocompatibility suitable for bone and joint repair. Using type I collagen as raw material and the principle of biomimetic mineralization for self-assembly of bone tissue, a new drug-loaded mineralized collagen implant was constructed by molecular coprecipitation with isoniazid. Its surface morphology, elemental composition, and porosity were characterized by field emission scanning electron microscope (SEM), X-ray diffraction (XRD), and pycnometer. The performance of the implant was gauged by sustained release and degradation, which were studied using an ultraviolet spectrophotometer and a simulated in vivo environment. The drug loading and encapsulation rates of the implants were (6.25 ± 0.48)% and (54 ± 2.34)%, respectively. The in vitro release time of the scaffold was more than 12 weeks and the degradation performance was excellent. The scaffold was then implanted into mice, and the inflammatory reaction of local tissue was observed by Haemotoxylin and Eosin (H&E) and Masson. The in vivo evaluation in mice showed that the scaffold was biocompatible. Overall, compared with traditional drug loading systems, the isoniazid biomimetic mineralized collagen implant constructed here has better drug release performance, biodegradability, and biocompatibility. This kind of collagen implant may find potential applications in tuberculous bone and joint repair.

Two-phase anaerobic digestion of lignocellulosic hydrolysate: Focusing on the acidification with different inoculum to substrate ratios and inoculum sources.

Biogas production from lignocellulosic hydrolysate is of great potential for lignocellulosic materials. Two-phase anaerobic digestion was proposed in this study. Acidogenic fermentation was carried out with corn straw hydrolysate as feedstock for volatile fatty acids (VFAs) production. Using anaerobic sludge (AnS), different inoculum to substrate ratios (ISRs) of 0.5:1, 1:1 and 2:1 were investigated. The highest VFAs yield was obtained at ISR of 0.5:1.VFAs composition analysis showed that butyric acid was the predominant acid, followed by acetic acid and propionic acid. The effects of AnS and aerobic sludge (AeS) on the acidogenic performance of hydrolysate were compared. The optimum VFA yields were 0.38 g/g COD-added for AnS and 0.32 g/g COD-added for AeS with HRT of 5 d, respectively. The bacterial diversities of inocula and digestates were analyzed by high-throughput sequencing. Two origins of inocula had distinct bacterial structures, but they did share core communities that included Firmicutes, Chloroflexi, Proteobacteria and Bacteroidetes at phylum level. The bacterial communities of both digestates changed significantly as compared with those in inoculum. Firmicutes was absolutely dominant in all the bacterial species. Therefore, the AeS could be an option as the acidogenic inoculum. The microbial information will be beneficial for the enrichment and acclimatization of microbes. In methanogenic process, VFAs obtained in acidogenic stage could be efficiently converted into methane. The ultimate methane yield at organic loading rate (OLR) of 8 g/L·d could reach 290 mL CH4/g COD-added and 279 mL CH4/g COD-added for AnS and AeS acidified digestate. Two-phase anaerobic digestion was proved to be suitable for bioconversion of lignocellulosic hydrolysate into biogas.

[The influence of porcelain-fused-to-metal on the expression level of IL-23 in gingival crevicular fluid].

PURPOSE: To investigate the role of IL-23 in the pathogenesis of periodontitis, and the influence of porcelain-fused-to-metal (PFM) on periodontal tissue and the expression level of IL-23. METHODS: The gingival crevicular fluid (GCF) samples were collected in 10 periodontally healthy individuals, 14 cases with gingivitis, 14 cases with gingivitis and PFM, and 14 cases with periodontitis and PFM. The teeth were detected and recorded the clinical parameters（GI, SBI, AL, PD）by Florida probe. The concentration of IL-23 in GCF was detected by ELISA assays.SPSS13.0 software package was used for statistical analysis. RESULTS: The expression of IL-23 in GCF of normal group (227.047±29.880) pg/mL was below inflammatory groups. A significant overexpression of IL-23 in GCF was detected in periodontitis with PFM group(511.327±138.846) pg/mL compared to gingivitis group (330.353±196.266) pg/mL (P<0.01) and gingivitis with PFM group (347.359±218.260) pg/mL (P<0.05). The expression level of IL-23 in GCF was positively correlated with clinical parameters (GI, SBI, AL, PD) (r>0.4, P<0.05). There was a high degree of periodontal destruction in gingivitis with PFM group compared to gingivitis group, and significant difference existed in AL (P<0.05) and PD (P<0.01). The change of IL-23 expression was most positively correlated with PD (r>0.5, P<0.01). CONCLUSIONS: IL-23 might play an important role in the pathogenesis of periodontitis. PFM could have influence on the destruction of periodontal tissues and the expression level of IL-23.

Boronate Affinity-Molecularly Imprinted Biocompatible Probe: An Alternative for Specific Glucose Monitoring.

A biocompatible probe for specific glucose recognition is based on photoinitiated boronate affinity-molecular imprinted polymers (BA-MIPs). The unique pre-self-assembly between glucose and boronic acids creates glucose-specific memory cavities in the BA-MIPs coating. As a result, the binding constant toward glucose was enhanced by three orders of magnitude. The BA-MIPs probe was applied to glucose determination in serum and urine and implanted into plant tissues for low-destructive and long-term in vivo continuous glucose monitoring.

[Effect of tamibarotene on innate immune response in the model of Porphyromonas gingivalis induced periodontitis].

OBJECTIVE: To investigate the effect of Am80 on innate immune response of Porphyromonas gingivalis (Pg) W83-induced periodontitis in mice. METHODS: Twenty-five mice were randomly divided into five groups, control group, PgW83-induced periodontitis group (periodontitis), Am80 (10 µg/d) treatment group (low-dose group), Am80 (50 µg/d) treatment group (middle-dose group), Am80 (100 µg/d) treatment group (high-dose group). The distance of alveolar bone resorption in each mouse was observed and measured by a dissecting microscope. Enzyme-linked immunosorbent assay (ELISA) was used to detect the level of serum anti-Pg specific IgG. The mRNA expression of interferon-γ (IFN-γ) and interleuking-12 (IL-12) in gingival tissues, draining lymph node and spleen were detected by real-time reverse transcriptase polymerase chain reaction (RT-PCR). The measurement data were statistically analyzed. RESULTS: The resorption rate in Am80 group [(121 ± 10)%] and high-dose of Am80 group [(108 ± 8)%] was significantly different with that in periodontitis mice [(133 ± 10)% ] (P < 0.05). The serum levels of anti-Pg specific IgG of the Am80 groups of different doses (0.437 ± 0.083, 0.566 ± 0.012, and 0.386 ± 0.078) were significantly lower than that of the periodontitis group (1.151 ± 0.433) (P < 0.001). Real-time quantitative PCR assay showed that after Am80 treatment, the IL-12 mRNA levels in the gingival tissues, lymph nodes and spleen of mice were reduced to 1.107 ± 0.088, 0.806 ± 0.220, and 0.668 ± 0.756, which were all significantly different with those in periodontitis (P < 0.01). Similarly, the relative expression of IFN-γ mRNA levels in gingival tissue, lymph nodes and spleen of mice were reduced to 8.898 ± 0.427, 16.654 ± 5.995, and 1.482 ± 0.033, which were significantly different with periodontitis (P < 0.001). CONCLUSIONS: Am80 can reduce the extent of inflammation and alleviate alveolar bone resorption by modulating innate immune response.

Accessory enzymes influence cellulase hydrolysis of the model substrate and the realistic lignocellulosic biomass.

The potential of cellulase enzymes in the developing and ongoing "biorefinery" industry has provided a great motivation to develop an efficient cellulase mixture. Recent work has shown how important the role that the so-called accessory enzymes can play in an effective enzymatic hydrolysis. In this study, three newest Novozymes Cellic CTec cellulase preparations (CTec 1/2/3) were compared to hydrolyze steam pretreated lignocellulosic substrates and model substances at an identical FPA loading. These cellulase preparations were found to display significantly different hydrolytic performances irrelevant with the FPA. And this difference was even observed on the filter paper itself when the FPA based assay was revisited. The analysis of specific enzyme activity in cellulase preparations demonstrated that different accessory enzymes were mainly responsible for the discrepancy of enzymatic hydrolysis between diversified substrates and various cellulases. Such the active role of accessory enzymes present in cellulase preparations was finally verified by supplementation with ß-glucosidase, xylanase and lytic polysaccharide monooxygenases AA9. This paper provides new insights into the role of accessory enzymes, which can further provide a useful reference for the rational customization of cellulase cocktails in order to realize an efficient conversion of natural lignocellulosic substrates.

A Weibull statistics-based lignocellulose saccharification model and a built-in parameter accurately predict lignocellulose hydrolysis performance.

Renewable energy from lignocellulosic biomass has been deemed an alternative to depleting fossil fuels. In order to improve this technology, we aim to develop robust mathematical models for the enzymatic lignocellulose degradation process. By analyzing 96 groups of previously published and newly obtained lignocellulose saccharification results and fitting them to Weibull distribution, we discovered Weibull statistics can accurately predict lignocellulose saccharification data, regardless of the type of substrates, enzymes and saccharification conditions. A mathematical model for enzymatic lignocellulose degradation was subsequently constructed based on Weibull statistics. Further analysis of the mathematical structure of the model and experimental saccharification data showed the significance of the two parameters in this model. In particular, the λ value, defined the characteristic time, represents the overall performance of the saccharification system. This suggestion was further supported by statistical analysis of experimental saccharification data and analysis of the glucose production levels when λ and n values change. In conclusion, the constructed Weibull statistics-based model can accurately predict lignocellulose hydrolysis behavior and we can use the λ parameter to assess the overall performance of enzymatic lignocellulose degradation. Advantages and potential applications of the model and the λ value in saccharification performance assessment were discussed.

Full-solution processed flexible organic solar cells using low-cost printable copper electrodes.

Full-solution-processed flexible organic solar cells (OSCs) are fabricated using low-cost and high-quality printable Cu electrodes, which achieve a power conversion efficiency as high as 2.77% and show remarkable stability upon 1000 bending cycles. This device performance is thought to be the best among all full-solution-processed OSCs reported in the literature using the same active materials. This printed Cu electrode is promising for application in roll-to-roll fabrication of flexible OSCs.

High ß-glucosidase secretion in Saccharomyces cerevisiae improves the efficiency of cellulase hydrolysis and ethanol production in simultaneous saccharification and fermentation.

Bioethanol production from lignocellulose is considered as a sustainable biofuel supply. However, the low cellulose hydrolysis efficiency limits the cellulosic ethanol production. The cellulase is strongly inhibited by the major end product cellobiose, which can be relieved by the addition of ß-glucosidase. In this study, three ß-glucosidases from different organisms were respectively expressed in Saccharomyces cerevisiae and the ß-glucosidase from Saccharomycopsis fibuligera showed the best activity (5.2 U/ml). The recombinant strain with S. fibuligera ß-glucosidase could metabolize cellobiose with a specific growth rate similar to the control strain in glucose. This recombinant strain showed higher hydrolysis efficiency in the cellulose simultaneous saccharification and fermentation, when using the Trichoderma reesei cellulase, which is short of the ß-glucosidase activity. The final ethanol concentration was 110% (using Avicel) and 89% (using acid-pretreated corncob) higher than the control strain. These results demonstrated the effect of ß-glucosidase secretion in the recombinant S. cerevisiae for enhancing cellulosic ethanol conversion.

The identification of and relief from Fe3+ inhibition for both cellulose and cellulase in cellulose saccharification catalyzed by cellulases from Penicillium decumbens.

Lignocellulosic biomass is an underutilized, renewable resource that can be converted to biofuels. The key step in this conversion is cellulose saccharification catalyzed by cellulase. In this work, the effect of metal ions on cellulose hydrolysis by cellulases from Penicillium decumbens was reported for the first time. Fe(3+) and Cu(2+) were shown to be inhibitory. Further studies on Fe(3+) inhibition showed the inhibition takes place on both enzyme and substrate levels. Fe(3+) treatment damages cellulases' capability to degrade cellulose and inhibits all major cellulase activities. Fe(3+) treatment also reduces the digestibility of cellulose, due to its oxidation. Treatment of Fe(3+)-treated cellulose with DTT and supplementation of EDTA to saccharification systems partially relieved Fe(3+) inhibition. It was concluded that Fe(3+) inhibition in cellulose degradation is a complicated process in which multiple inhibition events occur, and that relief from Fe(3+) inhibition can be achieved by the supplementation of reducing or chelating agents.

[Comparison of the IL-27 level in gingival crevicular fluid of cross-quadrant and the upper and lower half-mouth subgingival scaling].

PURPOSE: To investigate the changes of IL-27 in gingival crevicular fluid (GCF) before and after treatment with different methods for chronic periodontitis. METHODS: Sixty patients with moderate or severe chronic periodontitis were selected as study group to divide into group A (cross-quadrant) and group B (upper and lower half-mouth) randomly. Another 30 healthy people were selected as group C. Gingival crevicular fluid of group A and B were collected at baseline and each week during treatment. At the same time, the clinical parameters including PD, AL, BI and PLI were recorded. And the levels of IL-27 in GCF were measured by ELISA. SPSS 17.0 software package was used for statistical analysis. RESULTS: The levels of IL-27 in GCF 2 and 3 weeks after treatment were higher in study group compared with those at baseline, while PD, AL, BI and PLI showed significant reduction. The changes except PLI in group A was more obvious than group B, which had a significant difference. After three-week treatment, IL-27 in group A had no remarkable difference compared with group C. There were significantly negative correlation between PD, AL, BI, PLI and IL-27. CONCLUSIONS: IL-27 in GCF can be considered as a potential target for prevention and treatment of chronic periodontitis. Compared with the upper and lower half-mouth subgingival scaling, cross-quadrant has more pronounced short-term effect.

Cellulolytic enzyme production and enzymatic hydrolysis for second-generation bioethanol production.

Second-generation bioethanol made from lignocellulosic biomass is considered one of the most promising biofuels. However, the enzymatic hydrolysis of the cellulose component to liberate glucose for ethanol fermentation is one of the major barriers for the process to be economically competitive because of the recalcitrance of feedstock. In this chapter, the progress on the understanding of the mechanisms of lignocellulose degradation, as well as the identification and optimization of fungal cellulases, cellulolytic strains, and cellulase production is reviewed. The physiologic functions and enzymatic mechanisms of two groups of enzymes involved in lignocellulose degradation, cellulases and hemicellulases, are discussed, and the synergism of the cellulase components during lignocellulose degradation is addressed. Furthermore, the methods for screening filamentous fungal strains capable of degrading lignocellulose are evaluated and the production of cellulases by these fungal strains is discussed. Aside from traditional mutagenesis for improving the secretion level and enzymatic activities of cellulases from filamentous fungal species, genetic engineering of strains and protein engineering on cellulase molecules are also highlighted.