Biocatalytic cascade to polysaccharide amination.

BACKGROUND: Chitin, the main form of aminated polysaccharide in nature, is a biocompatible, polycationic, and antimicrobial biopolymer used extensively in industrial processes. Despite the abundance of chitin, applications thereof are hampered by difficulties in feedstock harvesting and limited structural versatility. To address these problems, we proposed a two-step cascade employing carbohydrate oxidoreductases and amine transaminases for plant polysaccharide aminations via one-pot reactions. Using a galactose oxidase from Fusarium graminearum for oxidation, this study compared the performance of CvATA (from Chromobacterium violaceum) and SpATA (from Silicibacter pomeroyi) on a range of oxidized carbohydrates with various structures and sizes. Using a rational enzyme engineering approach, four point mutations were introduced on the SpATA surface, and their effects on enzyme activity were evaluated. RESULTS: Herein, a quantitative colorimetric assay was developed to enable simple and accurate time-course measurement of the yield of transamination reactions. With higher operational stability, SpATA produced higher product yields in 36 h reactions despite its lower initial activity. Successful amination of oxidized galactomannan by SpATA was confirmed using a deuterium labeling method; higher aminated carbohydrate yields achieved with SpATA compared to CvATA were verified using HPLC and XPS. By balancing the oxidase and transaminase loadings, improved operating conditions were identified where the side product formation was largely suppressed without negatively impacting the product yield. SpATA mutants with multiple alanine substitutions besides E407A showed improved product yield. The E407A mutation reduced SpATA activity substantially, supporting its predicted role in maintaining the dimeric enzyme structure. CONCLUSIONS: Using oxidase-amine transaminase cascades, the study demonstrated a fully enzymatic route to polysaccharide amination. Although the activity of SpATA may be further improved via enzyme engineering, the low operational stability of characterized amine transaminases, as a result of low retention of PMP cofactors, was identified as a key factor limiting the yield of the designed cascade. To increase the process feasibility, future efforts to engineer improved SpATA variants should focus on improving the cofactor affinity, and thus the operational stability of the enzyme.

Functional screening pipeline to uncover laccase-like multicopper oxidase enzymes that transform industrial lignins.

Laccase-like multicopper oxidases are recognized for their potential to alter the reactivity of lignins for application in value-added products. Typically, model compounds are employed to discover such enzymes; however, they do not represent the complexity of industrial lignin substrates. In this work, a screening pipeline was developed to test enzymes simultaneously on model compounds and industrial lignins. A total of 12 lignin-active fungal multicopper oxidases were discovered, including 9 enzymes active under alkaline conditions (pH 11.0). Principal component analysis revealed the poor ability of model compounds to predict enzyme performance on industrial lignins. Additionally, sequence similarity analyses grouped these enzymes with Auxiliary Activity-1 sub-families with few previously characterized members, underscoring their taxonomic novelty. Correlation between the lignin-activity of these enzymes and their taxonomic origin, however, was not observed. These are critical insights to bridge the gap between enzyme discovery and application for industrial lignin valorization.

Value of ultrasound-guided synovial biopsy for the diagnosis of infectious arthritis.

Objectives: To determine the value of ultrasound (US)-guided synovial biopsy for the diagnosis of infectious arthritis that could not be detected by other modalities. Material and methods: This descriptive study was conducted among 37 patients with arthritis (3 with shoulder arthritis, 2 with elbow arthritis, 7 with wrist arthritis, 15 with hip arthritis, 4 with knee arthritis, and 5 with ankle arthritis) who underwent US-guided synovial biopsy at Hanoi Medical University Hospital for the diagnosis of infec-tious arthritis that could not be detected by infection laboratory tests, imaging, and/or joint fluid culture. The results of US-guided synovial biopsy were positive for infectious arthritis when those of pathologi-cal analyses, bacterial cultures, and/or polymerase chain reaction test for tuberculosis were positive. The final diagnosis established when the patients were discharged from the hospital was compared with the US-guided synovial biopsy results to calculate the sensitivity and specificity for the diagnosis of infectious arthritis. Results: The median age of the patients was 60 years (range: 22-79 years), and two thirds were women. Infectious arthritis was determined as the final diagnosis in 18 patients. There was no significant difference in the infection laboratory test results, synovial thickness, or magnetic resonance imaging features apart from soft tissue abscess between the infectious and non-infectious arthritis groups (P > 0.05). The US-guided synovial biopsy results were positive in 17 patients. Compared with the sensitivity and specificity of the final diagnosis, those of the US-guided synovial biopsy results for the diagnosis of infectious arthritis were 94.4% and 100%, respectively. The Numerical Rating Scale score was ≤3 in most patients. There were neither vascular nor neurologic complications among the patients. Conclusion: Imaging features and laboratory test results are non-specific for infectious arthritis. US-guided synovial biopsy is a well-tolerated, safe method that has a high value for the diagnosis of infectious arthritis. This modality should then be recommended for patients with unclassified arthritis.

Investigating the impact of a national educational program on patient adherence to osteoporosis medications.

Interrupted time series analysis (ITS) measured improvements in osteoporosis medication adherence after a national education program. The proportion of patients who were adherent to treatment increased following the program. INTRODUCTION: The NPS MedicineWise osteoporosis program, implemented nationally in 2015-2016 in Australia, sought to improve adherence to osteoporosis medicines using evidence-based multifaceted large-scale educational interventions targeting general practitioners. METHODS: We undertook a retrospective, observational study using ITS analysis from 1 December 2011 to 31 December 2019 using a 10% sample of Pharmaceutical Benefits Scheme (PBS) dispensing data for 71,093 patients ≥ 45 years. The adherence measure was the percentage of patients with a proportion of days covered (PDC) ≥ 80%. RESULTS: The program significantly increased adherence to osteoporosis medicines. After 12 months, the estimated adherence rate with the program was 48.4% (95% CI, 47.4-49.4%). Without the program, adherence would have fallen to 43.5% (95% CI, 42.5-44.5%). There was a further increase in adherence by the end of the study period (44 months after the program). Among patients prescribed denosumab only, despite a significant increase in adherence following the program, adherence rates were overall sub-optimal (65.0% 12 months following the program). CONCLUSIONS: The NPS MedicineWise osteoporosis program significantly increased osteoporosis medicine adherence. The program changed primary care prescriber behavior and improved treatment adherence. However, some patients had a period of treatment discontinuation, placing them at increased risk of fracture. A focused program emphasizing the importance of long-term adherence with denosumab (including switching to bisphosphonates if treatment is discontinued) may be warranted to further improve the quality use of osteoporosis treatment in Australia.

Near-Suicide Phenomenon: An Investigation into the Psychology of Patients with Serious Illnesses Withdrawing from Treatment.

Patients with serious illnesses or injuries may decide to quit their medical treatment if they think paying the fees will put their families into destitution. Without treatment, it is likely that fatal outcomes will soon follow. We call this phenomenon "near-suicide". This study attempted to explore this phenomenon by examining how the seriousness of the patient's illness or injury and the subjective evaluation of the patient's and family's financial situation after paying treatment fees affect the final decision on the treatment process. Bayesian Mindsponge Framework (BMF) analytics were employed to analyze a dataset of 1042 Vietnamese patients. We found that the more serious the illnesses or injuries of patients were, the more likely they were to choose to quit treatment if they perceived that paying the treatment fees heavily affected their families' financial status. Particularly, only one in four patients with the most serious health issues who thought that continuing the treatment would push themselves and their families into destitution would decide to continue the treatment. Considering the information-filtering mechanism using subjective cost-benefit judgments, these patients likely chose the financial well-being and future of their family members over their individual suffering and inevitable death. Our study also demonstrates that mindsponge-based reasoning and BMF analytics can be effective in designing and processing health data for studying extreme psychosocial phenomena. Moreover, we suggest that policymakers implement and adjust their policies (e.g., health insurance) following scientific evidence to mitigate patients' likelihood of making "near-suicide" decisions and improve social equality in the healthcare system.

Antifouling Properties of Pluronic and Tetronic Surfactants in Digital Microfluidics.

Fouling at liquid-solid interfaces is a pernicious problem for a wide range of applications, including those that are implemented by digital microfluidics (DMF). There are several strategies that have been used to combat surface fouling in DMF, the most common being inclusion of amphiphilic surfactant additives in the droplets to be manipulated. Initial studies relied on Pluronic additives, and more recently, Tetronic additives have been used, which has allowed manipulation of complex samples like serum and whole blood. Here, we report our evaluation of 19 different Pluronic and Tetronic additives, with attempts to determine (1) the difference in antifouling performance between the two families, (2) the structural similarities that predict exceptional antifouling performance, and (3) the mechanism of the antifouling behavior. Our analysis shows that both Pluronic and Tetronic additives with modest molar mass, poly(propylene oxide) (PPO) ≥50 units, poly(ethylene oxide) (PEO) mass percentage ≤50%, and hydrophilic-lipophilic balance (HLB) ca. 13-15 allow for exceptional antifouling performance in DMF. The most promising candidates, P104, P105, and T904, were able to support continuous movement of droplets of serum for more than 2 h, a result (for devices operating in air) previously thought to be out of reach for this technique. Additional results generated using device longevity assays, intrinsic fluorescence measurements, dynamic light scattering, asymmetric flow field flow fractionation, supercritical angle fluorescence microscopy, atomic force microscopy, and quartz crystal microbalance measurements suggest that the best-performing surfactants are more likely to operate by forming a protective layer at the liquid-solid interface than by complexation with proteins. We propose that these results and their implications are an important step forward for the growing community of users of this technique, which may provide guidance in selecting surfactants for manipulating biological matrices for a wide range of applications.

Implications of climate change and drought on water requirements in a semi-mountainous region of the Vietnamese Mekong Delta.

As the backbone of Vietnam's economy, the country has recently established a number of policies for promoting and investing in smart agriculture in the Mekong Delta, the country's largest agricultural hub, to foster overall socio-economic development. However, water remains a critical constraint for crop production, with progress being hindered by water scarcity and quality issues, and compounded by socio-economic transformation and climate change. Considering these challenges, this study used the CROPWAT model and a wide spectrum of climate change scenarios to investigate future total water demands in the 2030s and 2050s as well as drought levels in two underdeveloped semi-mountainous reservoir catchments, i.e., O Ta Soc and O Tuk Sa in An Giang province. The results suggest that the usable storage capacity of the O Ta Soc reservoir will increase to 650,000 m3 to meet water supply demands under all climate change scenarios and the medium-term, moderate drought conditions. The useable storage capacity of the O Tuk Sa reservoir will also be increased to 880,000 m3 and the irrigation area would see a marked 70% reduction compared to its design irrigation. Under these circumstances, the O Tuk Sa reservoir will continue to supply water under all climate change scenarios and medium-term droughts. As a core element for strategic planning and to ensure efficient management of water resources, the results highlight the importance of estimating potential runoff and rainfall in semi-mountainous reservoir catchments under various drought conditions in order to propose the suitable expansion of the useable water storage capacities.

Proteome of the Wood Decay Fungus Fomitopsis pinicola Is Altered by Substrate.

The brown rot fungus Fomitopsis pinicola efficiently depolymerizes wood cellulose via the combined activities of oxidative and hydrolytic enzymes. Mass spectrometric analyses of culture filtrates identified specific proteins, many of which were differentially regulated in response to substrate composition.

An SCPPPQ1/LAM332 protein complex enhances the adhesion and migration of oral epithelial cells: Implications for dentogingival regeneration.

Common periodontal disease treatment procedures often fail to restore the structural integrity of the junctional epithelium (JE), the epithelial attachment of the gum to the tooth, leaving the tooth-gum interface prone to bacterial colonization. To address this issue, we introduced a novel bio-inspired protein complex comprised of a proline-rich enamel protein, SCPPPQ1, and laminin 332 (LAM332) to enhance the JE attachment. Using quartz crystal microbalance with dissipation monitoring (QCM-D), we showed that SCPPPQ1 and LAM332 interacted and assembled into a protein complex with high-affinity adsorption of 5.9e-8 [M] for hydroxyapatite (HA), the main component of the mineralized tooth surfaces. We then designed a unique shear device to study the adhesion strength of the oral epithelial cells to HA. The SCPPPQ1/LAM332 complex resulted in a twofold enhancement in adhesion strength of the cells to HA compared to LAM332 (from 31 dyn/cm2 to 63 dyn/cm2). In addition, using a modified wound-healing assay, we showed that gingival epithelial cells demonstrated a significantly high migration rate of 2.7 ± 0.24 µm/min over SCPPPQ1/LAM332-coated surfaces. Our collective data show that this protein complex has the potential to be further developed in designing a bioadhesive to enhance the JE attachment and protect the underlying connective tissue from bacterial invasion. However, its efficacy for wound healing requires further testing in vivo. STATEMENT OF SIGNIFICANCE: This work is the first functional study towards understanding the combined role of the enamel protein SCPPPQ1 and laminin 332 (LAM332) in the epithelial attachment of the gum, the junctional epithelium (JE), to the tooth hydroxyapatite surfaces. Such studies are essential for developing therapeutic approaches to restore the integrity of the JE in the destructive form of gum infection. We have developed a model system that provided the first evidence of the strong interaction between SCPPPQ1 and LAM332 on hydroxyapatite surfaces that favored protein adsorption and subsequently oral epithelial cell attachment and migration. Our collective data strongly suggested using the SCPPPQ1/LAM332 complex to accelerate the reestablishment of the JE after surgical gum removal to facilitate gum regeneration.

Enzymatic synthesis of kraft lignin-acrylate copolymers using an alkaline tolerant laccase.

Softwood kraft lignin is a major bioresource relevant to the production of sustainable bio-based products. Continued challenges to lignin valorization, however, include poor solubility in organic solvents and in aqueous solutions at neutral pH. Herein, an alkaline tolerant laccase was used to graft acrylate functionalities onto softwood kraft lignin, which is expected to enhance the reactivity of lignin with isocyanate when producing bio-based polyurethanes. Proton nuclear magnetic resonance, Fourier-transform infrared spectroscopy, and high-performance liquid chromatography were used to confirm successful grafting of the acrylate monomer onto lignin and verify the importance of including tert-butyl hydroperoxide as an initiator in the grafting reaction. Laccase-mediated grafting of softwood kraft lignin under alkaline conditions produced lignin products with approximately 30% higher hydroxyl value and higher reactivity toward isocyanate. The reported enzymatic and aqueous process presents an opportunity for the sustainable valorization of softwood kraft lignin. KEY POINTS: • Softwood kraft lignin displayed high phenolic hydroxyl content, polydispersity index and average molecular weight • Grafting hydroxyethyl acrylate (HEA) monomer onto kraft lignin by laccase was successful at 60 °C and alkaline conditions • Lignin-HEA grafted copolymer showed an increase in total OH value and an increase in average molecular weight.

Are market mechanisms associated with alcohol and other drug treatment outcomes?

BACKGROUND AND AIMS: The configuration of alcohol and other drug treatment service systems has been influenced by the uptake of market mechanisms for treatment funding and purchasing. This study measured the impact of market mechanisms for funding and purchasing alcohol and drug treatment services on client outcomes. DESIGN: An observational cross-sectional study, employing multi-level analysis: episodes of care data, nested within person-level data, nested within treatment site and nested within organization. SETTING AND PARTICIPANTS: One hundred and seventy-eight alcohol and other drug treatment service sites in Australia. MEASUREMENTS: Client outcome variables were length of stay and successful treatment completion. Predictor variables were competitive tendering, number of funding contracts, recurrent funding, the ratio of episodes to staff, type of professions, years of clinical experience, staff turnover and type of provider (government; non-government). Analyses controlled for drug type, type of treatment received and client characteristics. FINDINGS: There were no significant associations between the procurement and contracting variables and length of stay [incidence rate ratios (IRRs) ranged between 1.01 and 1.07, all P > 0.05; Bayes factors (BF) < 0.03], and inconclusive results for treatment completion [odds ratios (ORs) ranged between 1.04 and 1.15, all P > 0.05, BF = 0.51-0.63]. Having an alcohol and other drug (AOD) work-force relative to an 'other' work-force (IRR = 0.79, P = 0.021) and lower case-loads (IRR = 0.99, P = 0.047) may be associated with longer stay in treatment. Receiving services from a government compared to non-government provider may also be associated with less treatment completion (OR = 0.34, P = 0.023, BF = 2.14). CONCLUSIONS: There appears to be no association between client outcomes and procurement and funding contract arrangements for alcohol and drug treatment services.

Enzymatic upgrading of heteroxylans for added-value chemicals and polymers.

Xylan is one of the most abundant, natural polysaccharides, and much recent interest focuses on upgrading heteroxylan to make use of its unique structures and chemistries. Significant progress has been made in the discovery and application of novel enzymes for debranching and modifying heteroxylans. Debranching enzymes include acetylxylan esterases, α-l-arabinofuranosidases and α-d-glucuronidases that release side groups from the xylan backbone to recover both biochemicals and less substituted xylans for polymer applications in food packaging or drug delivery systems. Besides esterases and hydrolases, many oxidoreductases including carbohydrate oxidases, lytic polysaccharide monooxygenases, laccases and peroxidases have been also applied to alter different types of xylans for improved physical and chemical properties. This review will highlight the recent discovery and application of enzymes for upgrading xylans for use as added-value chemicals and in functional polymers.

The association between involuntary alcohol treatment and subsequent emergency department visits and hospitalizations: a Bayesian analysis of treated patients and matched controls.

BACKGROUND AND AIMS: Many nations have provisions for involuntary treatment of alcohol dependence where the person is at serious risk of harm to themselves. To date, there has been little thorough evaluation of its effectiveness. This study aimed to determine if there were differences between involuntary and voluntary treatment for alcohol dependence on subsequent emergency and hospital care. DESIGN: A retrospective cohort design using linked routinely collected administrative data on health-care utilization. SETTING: Hospital and community-based alcohol treatment, New South Wales, Australia. PARTICIPANTS: A total of 231 patients who were involuntarily treated for alcohol dependence and 231 matched controls who received treatment as usual within the period May 2012 to April 2018. INTERVENTION AND COMPARATOR: Involuntary treatment comprised a 28-day mandated hospital admission which included supervised withdrawal, comprehensive assessment, rehabilitation and support followed by voluntary aftercare support for up to 6 months. Treatment as usual comprised three not mutually exclusive forms of intensive voluntary alcohol treatment: withdrawal management, rehabilitation and pharmacotherapies for alcohol dependence. MEASUREMENTS: Outcome measures: changes in the number of emergency department (ED) visits and number of unplanned hospital admissions 12 months before and 12 months after completion of index treatment. FINDINGS: Both groups showed a reduction in ED visits (incidence rate ratio (IRR) = 0.56, 95% credible intervals (CrI) = 0.39-0.78) and unplanned hospital admissions (IRR = 0.49, 95% CrI = 0.37-0.65). There was no statistically significant difference between the two groups (IRR = 0.77, 95% CrI = 0.58-1.03 for ED visits and IRR = 0.79, 95% CrI = 0.62-1.01 for hospital admissions). The Bayes factors were 0.925 and 0.936 for ED visits and unplanned hospital admissions, respectively, interpreted as weak evidence in support of the null hypothesis of no difference between the interventions. CONCLUSIONS: Involuntary treatment of alcohol dependence was associated with reduced health service utilization in the year following treatment, and the outcomes did not differ from those of a matched control group.

Telephone-Based Smoking Cessation Counseling Service: Satisfaction and Outcomes in Vietnamese Smokers.

BACKGROUND: As a method to acknowledge the devastating health and economic impacts of tobacco usage worldwide, telephone-based tobacco cessation counseling services have emerged as a potential tool to aid people in their quitting process. This study explores the satisfaction of smokers who use the QUITLINE service and factors associated with their quit attempts and cessation. METHODS: A cross-sectional survey of 110 participants was conducted from June to July 2016 at the Respiratory Center at Bach Mai Hospital, Hanoi, Vietnam. Multivariate logistic regression was used, and it was found that the percentage of people quitting smoking increased after using the service. RESULTS: In total, 65.5% of participants were completely satisfied with the counseling service. The mean score of staff/s capacity/responsiveness, motivation, and service convenience were 4.37 ± 0.78, 4.30 ± 0.81, and 4.27 ± 0.66, respectively. The smoking relapse rate was relatively high at 58.3%, which mainly resulted from cravings and busy work (26.2% and 14.3%, respectively). A higher satisfaction score in "Staffs' capacity and responsiveness" was negatively associated with "ever tried to quit smoking in consecutive 24 h" and actually quit smoking after receiving counseling. Meanwhile, a higher score in the "Motivation" domain was positively associated with both quit attempt indicators as well as actually quitting smoking after receiving counseling (OR = 9.48; 95%CI = 2.27; 39.57). CONCLUSIONS: These results suggest that it is crucial for decision makers to place more focus on countermeasures for smoking relapse and to strengthen the capacity of staff, especially in motivating clients. Interventions should also be maintained throughout a long period of time to prevent relapse.

The Comparative Abilities of a Small Laccase and a Dye-Decoloring Peroxidase From the Same Bacterium to Transform Natural and Technical Lignins.

The relative ability of the small laccase (sLac) and dye-decoloring peroxidase (DyP2) from Amycolatopsis sp. 75iv2 to transform a variety of lignins was investigated using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The enzymes modified organosolv hardwood lignin to different extents even in the absence of an added mediator. More particularly, sLac decreased the lignin modification metric S (S-lignin)/Ar (total aromatics) by 58% over 16h, while DyP2 lowered this ratio by 31% in the absence of exogenous H2O2. When used on their own, both sLac and DyP2 also modified native lignin present in aspen wood powder, albeit to lesser extents than in the organosolv lignin. The addition of ABTS for sLac and Mn2+ as well as H2O2 for DyP2 led to increased lignin modification in aspen wood powder as reflected by a decrease in the G/Ar metric by up to a further 13%. This highlights the importance of exogenous mediators for transforming lignin within its native matrix. Furthermore, the addition of ABTS reduced the selectivity of sLac for S-lignin over G-lignin, indicating that the mediator also altered the product profiles. Finally, when sLac was included in reactions containing DyP2, in part to generate H2O2 in situ, the relative abundance of lignin products differed from individual enzymatic treatments. Overall, these results identify possible routes to tuning lignin modification or delignification through choice of enzyme and mediator. Moreover, the current study expands the application of ToF-SIMS to evaluating enzyme action on technical lignins, which can accelerate the discovery and engineering of industrially relevant enzymes for lignin valorization.

Retracted and Republished from: "Substrate-Specific Differential Gene Expression and RNA Editing in the Brown Rot Fungus Fomitopsis pinicola"

Wood-decaying fungi tend to have characteristic substrate ranges that partly define their ecological niche. Fomitopsis pinicola is a brown rot species of Polyporales that is reported on 82 species of softwoods and 42 species of hardwoods. We analyzed gene expression levels of F. pinicola from submerged cultures with ground wood powder (sampled at 5 days) or solid wood wafers (sampled at 10 and 30 days), using aspen, pine, and spruce substrates (aspen was used only in submerged cultures). Fomitopsis pinicola expressed similar sets of wood-degrading enzymes typical of brown rot fungi across all culture conditions and time points. Nevertheless, differential gene expression was observed across all pairwise comparisons of substrates and time points. Genes exhibiting differential expression encode diverse enzymes with known or potential function in brown rot decay, including laccase, benzoquinone reductase, aryl alcohol oxidase, cytochrome P450s, and various glycoside hydrolases. Comparing transcriptomes from submerged cultures and wood wafers, we found that culture conditions had a greater impact on global expression profiles than substrate wood species. These findings highlight the need for standardization of culture conditions in studies of gene expression in wood-decaying fungi. IMPORTANCE All species of wood-decaying fungi occur on a characteristic range of substrates (host plants), which may be broad or narrow. Understanding the mechanisms that allow fungi to grow on particular substrates is important for both fungal ecology and applied uses of different feedstocks in industrial processes. We grew the wood-decaying polypore Fomitopsis pinicola on three different wood species­aspen, pine, and spruce­under various culture conditions. We found that F. pinicola is able to modify gene expression (transcription levels) across different substrate species and culture conditions. Many of the genes involved encode enzymes with known or predicted functions in wood decay. This study provides clues to how wood-decaying fungi may adjust their arsenal of decay enzymes to accommodate different host substrates.

Online interventions to reduce stigma towards population groups affected by blood borne viruses in Australia.

BACKGROUND: Stigmatising attitudes and behaviours by others can have a range of negative effects for population groups and individual people affected by blood borne viruses. The reduction of stigma is a major goal within current Australian national health strategies, however, there is a lack of evidence regarding effective interventions to achieve this goal. Drawing on Allport's (1954) intergroup contact theory, this study aimed to evaluate the effectiveness of an online stigma reduction intervention implemented with the Australian public. METHODS: The study was conducted between February and May 2020. Australian adults recruited via Facebook advertising were randomly allocated to a control group (n=316) or one of five intervention groups: people living with HIV (n=320), people living with hepatitis C (n=347), people living with hepatitis B (n=333), people who inject drugs (n=316), or sex workers (n=296). Participants viewed a short video depicting lived experiences of their assigned group. Participants completed attitudinal measures about the group before and immediately after the video, and then at three-month follow-up. These measures related to overall attitudes towards the group, controllability of the stigmatised condition/behaviour, desire to maintain personal distance from the group, and opinions regarding treatment of the group in health care and public policy. Longitudinal changes in attitudes were analysed using a mixed effects regression model with maximum likelihood estimation. RESULTS: Across each of the intervention groups, reductions in negative attitudes were found immediately after watching the videos on almost all outcome measures. By three-month follow-up, the HIV intervention group demonstrated long-term improvements in relation to personal distance compared to the control group, and the hepatitis B intervention group demonstrated long-term improvements in relation to attitudes and personal distance compared to the control group. Across intervention and control groups, long-term reductions in negative attitudes were found in relation to HIV controllability, hepatitis B controllability and opinions, hepatitis C controllability and opinions, and injecting drug use attitudes and opinions. CONCLUSION: Brief online videos depicting priority populations groups demonstrated positive results in terms of reducing some stigmatising attitudes towards those groups amongst members of the Australian public. Online contact interventions have the potential to be scaled up and rolled out across jurisdictions at national and international levels. These findings suggest that these interventions could be an effective way to contribute to the reduction of stigma and discrimination towards populations affected by blood borne viruses.

Discovery of fungal oligosaccharide-oxidising flavo-enzymes with previously unknown substrates, redox-activity profiles and interplay with LPMOs.

Oxidative plant cell-wall processing enzymes are of great importance in biology and biotechnology. Yet, our insight into the functional interplay amongst such oxidative enzymes remains limited. Here, a phylogenetic analysis of the auxiliary activity 7 family (AA7), currently harbouring oligosaccharide flavo-oxidases, reveals a striking abundance of AA7-genes in phytopathogenic fungi and Oomycetes. Expression of five fungal enzymes, including three from unexplored clades, expands the AA7-substrate range and unveils a cellooligosaccharide dehydrogenase activity, previously unknown within AA7. Sequence and structural analyses identify unique signatures distinguishing the strict dehydrogenase clade from canonical AA7 oxidases. The discovered dehydrogenase directly is able to transfer electrons to an AA9 lytic polysaccharide monooxygenase (LPMO) and fuel cellulose degradation by LPMOs without exogenous reductants. The expansion of redox-profiles and substrate range highlights the functional diversity within AA7 and sets the stage for harnessing AA7 dehydrogenases to fine-tune LPMO activity in biotechnological conversion of plant feedstocks.

Structural characterization of the family GH115 α-glucuronidase from Amphibacillus xylanus yields insight into its coordinated action with α-arabinofuranosidases.

The coordinated action of carbohydrate-active enzymes has mainly been evaluated for the purpose of complete saccharification of plant biomass (lignocellulose) to sugars. By contrast, the coordinated action of accessory hemicellulases on xylan debranching and recovery is less well characterized. Here, the activity of two family GH115 α-glucuronidases (SdeAgu115A from Saccharophagus degradans, and AxyAgu115A from Amphibacillus xylanus) on spruce arabinoglucuronoxylan (AGX) was evaluated in combination with an α-arabinofuranosidase from families GH51 (AniAbf51A, aka E-AFASE from Aspergillus niger) and GH62 (SthAbf62A from Streptomyces thermoviolaceus). The α-arabinofuranosidases boosted (methyl)-glucuronic acid release by SdeAgu115A by approximately 50 % and 30 %, respectively. The impact of the α-arabinofuranosidases on AxyAgu115A activity was comparatively low, motivating its structural characterization. The crystal structure of AxyAgu115A revealed increased length and flexibility of the active site loop compared to SdeAgu115A. This structural difference could explain the ability of AxyAgu115A to accommodate more highly substituted arabinoglucuronoxylan, and inform enzyme selections for improved AGX recovery and use.