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The Consortium for Top-Down Proteomics (www.topdownproteomics.org) launched the present study to assess the current state of top-down mass spectrometry (TD MS) and middle-down mass spectrometry (MD MS) for characterizing monoclonal antibody (mAb) primary structures, including their modifications. To meet the needs of the rapidly growing therapeutic antibody market, it is important to develop analytical strategies to characterize the heterogeneity of a therapeutic product's primary structure accurately and reproducibly. The major objective of the present study is to determine whether current TD/MD MS technologies and protocols can add value to the more commonly employed bottom-up (BU) approaches with regard to confirming protein integrity, sequencing variable domains, avoiding artifacts, and revealing modifications and their locations. We also aim to gather information on the common TD/MD MS methods and practices in the field. A panel of three mAbs was selected and centrally provided to 20 laboratories worldwide for the analysis: Sigma mAb standard (SiLuLite), NIST mAb standard, and the therapeutic mAb Herceptin (trastuzumab). Various MS instrument platforms and ion dissociation techniques were employed. The present study confirms that TD/MD MS tools are available in laboratories worldwide and provide complementary information to the BU approach that can be crucial for comprehensive mAb characterization. The current limitations, as well as possible solutions to overcome them, are also outlined. A primary limitation revealed by the results of the present study is that the expert knowledge in both experiment and data analysis is indispensable to practice TD/MD MS.

Native mass spectrometric analysis of TPR2A and GrpE with unpurified peptides derived from limited proteolysis of their respective PPI partners (HSP90 C-terminus and DnaK) facilitated efficient, qualitative identification of interfacial epitopes involved in transient PPI formation. Application of this approach can assist in elucidating interfaces of currently uncharacterised transient PPIs. [ABSTRACT FROM AUTHOR]

Carboxylic ester hydrolases with the capacity to degrade polyesters are currently highly sought after for their potential use in the biological degradation of PET and other chemically synthesized polymers. Here, we describe MarCE, a carboxylesterase family protein identified via genome mining of a Maribacter sp. isolate from the marine sponge Stelligera stuposa. Based on phylogenetic analysis, MarCE and its closest relatives belong to marine‐associated genera from the Cytophaga–Flavobacterium–Bacteroides taxonomic group and appear evolutionarily distinct to any homologous carboxylesterases that have been studied to date in terms of structure or function. Molecular docking revealed putative binding of BHET, a short‐chain PET derivative, onto the predicted MarCE three‐dimensional structure. The synthetic ester‐degrading activity of MarCE was subsequently confirmed by MarCE‐mediated hydrolysis of 2 mM BHET substrate, indicated by the release of its breakdown products MHET and TPA, which were measured, respectively, as 1.28 and 0.12 mM following 2‐h incubation at 30°C. The findings of this study provide further insight into marine carboxylic ester hydrolases, which have the potential to display unique functional plasticity resulting from their adaptation to complex and fluctuating marine environmentsw. [ABSTRACT FROM AUTHOR]

A teachers' practice cannot be characterised by a single lesson, hence comparison is best made with lesson sequences that better sample the diversity of a teacher's practice. In this study, we video recorded lesson sequences in four Year 8 mathematics classrooms, as well as interviewed each of the four teachers in Brunei Darussalam. Because of our methodology and based on the findings from the richness in the data that was collected, there were some features in the video and interview data that emerged. One of the features is the significant short utterances made by the students as well as their respective teachers, and the extent of the teachers' own and their students' questioning behaviours in the lessons as perceived by the teachers themselves during the video-stimulated recall interviews. In the four Brunei classrooms that we studied, most of the lessons were so rushed, the teachers did most of the talking and when teachers and students do interact, it almost always involved faster-paced exchanges between them. Thus, restricting students to single words ("yes" or "no") or short choral responses. Overall, the findings appear to indicate that short utterances implied that there were less (or even no) opportunities for fuller student participation in classroom discussions.

Lignin is a complex heteroaromatic polymer which is one of the most abundant and diverse biopolymers on the planet. It comprises approximately one third of all woody plant matter, making it an attractive candidate as an alternative, renewable feedstock to petrochemicals to produce fine chemicals. However, the inherent complexity of lignin makes it difficult to analyse and characterise using common analytical techniques, proving a hindrance to the utilisation of lignin as a green chemical feedstock. Herein we outline the tracking of lignin degradation by an alkaliphilic laccase in a semi-quantitative manner using a combined chemical analysis approach using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterise shifts in chemical diversity and relative abundance of ions, and NMR to highlight changes in the structure of lignin. Specifically, an alkaliphilic laccase was used to degrade an industrially relevant lignin, with compounds such as syringaresinol being almost wholly removed (95%) after 24 hours of treatment. Structural analyses reinforced these findings, indicating a >50% loss of NMR signal relating to β-β linkages, of which syringaresinol is representative. Ultimately, this work underlines a combined analytical approach that can be used to gain a broader semi-quantitative understanding of the enzymatic activity of laccases within a complex, non-model mixture. [ABSTRACT FROM AUTHOR]

The major premise of this project is that teachers learn from the act of teaching a lesson. Rather than asking "What must a teacher already know in order to practice effectively?", this project asks "What might a teacher learn through their activities in the classroom and how might this learning be optimised?" In this project, controlled conditions are created utilising purposefully designed and trialled lesson plans to investigate the process of teacher knowledge construction, with teacher selective attention proposed as a key mediating variable. In order to investigate teacher learning through classroom practice, the project addresses the following questions: To what classroom objects, actions and events do teachers attend and with what consequence for their learning? Do teachers in different countries attend to different classroom events and consequently derive different learning benefits from teaching a lesson? This international project combines focused case studies with an online survey of mathematics teachers' selective attention and consequent learning in Australia, China and Germany. Data include the teacher's adaptation of a pre-designed lesson, the teacher's actions during the lesson, the teacher's reflective thoughts about the lesson and, most importantly, the consequences for the planning and delivery of a second lesson. The combination of fine-grained, culturally situated case studies and large-scale online survey provides mutually informing benefits from each research approach. The research design, so constituted, offers the means to a new and scalable vision of teacher learning and its promotion.

Heterostructures formed by quantum Hall systems and superconductors haverecently been shown to support widely coveted Majorana fermion zero-modes andstill more exotic `parafermionic' generalizations. Here we establish thatprobing such zero-modes using quantum Hall edge states yields non-localtransport signatures that pave the way towards a variety of novel circuitelements. In particular, we demonstrate quite generally that at low energiesthe zero-modes convert chirally moving quasiparticles into oppositely chargedquasiholes propagating in the same direction---that is, they swap the sign ofthe chiral edge currents. One may then construct new and potentially usefulcircuit elements using this `perfect Andreev conversion' process, includingsuperconducting current and voltage mirrors as well as transistors forfractional charge currents. Characterization of these circuit elements shouldprovide striking evidence of the zero-mode physics.

Non-Abelian anyons promise to reveal spectacular features of quantum mechanics that could ultimately provide the foundation for a decoherence-free quantum computer. A key breakthrough in the pursuit of these exotic particles originated from Read and Green's observation that the Moore-Read quantum Hall state and a (relatively simple) two-dimensional p + ip superconductor both support so-called Ising non-Abelian anyons. Here, we establish a similar correspondence between the Z3 Read-Rezayi quantum Hall state and a novel two-dimensional superconductor in which charge-2e Cooper pairs are built from fractionalized quasiparticles. In particular, both phases harbor Fibonacci anyons that-unlike Ising anyons-allow for universal topological quantum computation solely through braiding. Using a variant of Teo and Kane's construction of non-Abelian phases from weakly coupled chains, we provide a blueprint for such a superconductor using Abelian quantum Hall states interlaced with an array of superconducting islands. Fibonacci anyons appear as neutral deconfined particles that lead to a twofold ground-state degeneracy on a torus. In contrast to a p + ip superconductor, vortices do not yield additional particle types, yet depending on nonuniversal energetics can serve as a trap for Fibonacci anyons. These results imply that one can, in principle, combine well-understood and widely available phases of matter to realize non-Abelian anyons with universal braid statistics. Numerous future directions are discussed, including speculations on alternative realizations with fewer experimental requirements.

The gut microbiota is increasingly recognised as a key player in influencing human health and changes in the gut microbiota have been strongly linked with many non-communicable conditions in humans such as type 2 diabetes, obesity and cardiovascular disease. However, characterising the molecular mechanisms that underpin these associations remains an important challenge for researchers. The gut microbiota is a complex microbial community that acts as a metabolic interface to transform ingested food (and other xenobiotics) into metabolites that are detected in the host faeces, urine and blood. Many of these metabolites are only produced by microbes and there is accumulating evidence to suggest that these microbe-specific metabolites do act as effectors to influence human physiology. For example, the gut microbiota can digest dietary complex polysaccharides (such as fibre) into short-chain fatty acids (SCFA) such as acetate, propionate and butyrate that have a pervasive role in host physiology from nutrition to immune function. In this review we will outline our current understanding of the role of some key microbial metabolites, such as SCFA, indole and bile acids, in human health. Whilst many studies linking microbial metabolites with human health are correlative we will try to highlight examples where genetic evidence is available to support a specific role for a microbial metabolite in host health and well-being. [ABSTRACT FROM AUTHOR]

The content and purpose of written unit plans in mathematics is an under-researched area. In this article, we provide a brief overview of research on teachers' planning processes and the place of mental and written plans. We report on data from a questionnaire completed by 357 teachers from Victorian Catholic primary schools, where we focused on possible elements of written unit plans for primary mathematics, and the relative importance which teachers attributed to these elements. We then discuss 48 written unit plans which were provided to us by primary schools from which the 357 teachers were drawn. There was considerable variation in the length, intended teaching time, and level of specification of key ideas in these plans. We discuss this variation, and some discrepancies between the ratings of teachers of the importance of certain elements and their presence in the plans we examined. We also suggest potentially productive areas of future enquiry.

Insights into teachers' planning of mathematics reported here were gathered as part of a broader project examining aspects of the implementation of the Australian curriculum in mathematics (and English). In particular, the responses of primary and secondary teachers to a survey of various aspects of decisions that inform their use of curriculum documents and assessment processes to plan their teaching are discussed. Teachers appear to have a clear idea of the overall topic as the focus of their planning, but they are less clear when asked to articulate the important ideas in that topic. While there is considerable diversity in the processes that teachers use for planning and in the ways that assessment information informs that planning, a consistent theme was that teachers make active decisions at all stages in the planning process. Teachers use a variety of assessment data in various ways, but these are not typically data extracted from external assessments. This research has important implications for those responsible for supporting teachers in the transition to the "Australian Curriculum: Mathematics."

Under the auspices of its 'Education Revolution', the Federal Labor Government is currently implementing a national curriculum for schools. Representing an important intervention into educational practice and governance, the Australian Curriculum offers a unique research opportunity, providing substantial scope for the examination of the changing systems and school-level practices entailed in large-scale curriculum reform. Research into the Australian Curriculum also presents a valuable opportunity to develop educational research methodologies that attend to the complex and multifaceted processes of curriculum reform, from systems to classrooms. Taking two of the disciplinary towers of modern curricula (English and mathematics) and Australia's two largest jurisdictions (New South Wales and Victoria) as the focus, this article draws on a three-year Australian Research Council Linkage Project to outline an approach to researching major curriculum reform.

The successful enzymatic degradation of polyester substrates has fueled worldwide investigation into the treatment of plastic waste using bio-based processes. Within this realm, marine-associated microorganisms have emerged as a promising source of polyester-degrading enzymes. In this work, we describe the hydrolysis of the synthetic polymer PET by SM14est, a polyesterase which was previously identified fromStreptomyces sp. SM14, an isolate of themarine sponge Haliclona simulans. The PET hydrolase activity of purified SM14est was assessed using a suspension-based assay and subsequent analysis of reaction products by UV-spectrophotometry and RP-HPLC. SM14est displayed a preference for high salt conditions, with activity significantly increasing at sodium chloride concentrations from 100mM up to 1,000mM. The initial rate of PET hydrolysis by SM14est was determined to be 0.004 s-1 at 45°C, which was increased by 5-fold to 0.02 s-1 upon addition of 500mM sodium chloride. Sequence alignment and structural comparison with known PET hydrolases, including the marine halophile PET6, and the highly efficient, thermophilic PHL7, revealed conserved features of interest. Based on this work, SM14est emerges as a useful enzyme that is more similar to key players in the area of PET hydrolysis, like PHL7 and IsPETase, than it is to its marine counterparts. Salt-tolerant polyesterases such as SM14est are potentially valuable in the biological degradation of plastic particles that readily contaminate marine ecosystems and industrial wastewaters. [ABSTRACT FROM AUTHOR]

Protein misfolding and aggregation into oligomeric and fibrillar structures is a common feature of many neurogenerative disorders. Single‐molecule techniques have enabled characterization of these lowly abundant, highly heterogeneous protein aggregates, previously inaccessible using ensemble averaging techniques. However, they usually rely on the use of recombinantly‐expressed labeled protein, or on the addition of amyloid stains that are not protein‐specific. To circumvent these challenges, we have made use of a high affinity antibody labeled with orthogonal fluorophores combined with fast‐flow microfluidics and single‐molecule confocal microscopy to specifically detect α‐synuclein, the protein associated with Parkinson's disease. We used this approach to determine the number and size of α‐synuclein aggregates down to picomolar concentrations in biologically relevant samples. [ABSTRACT FROM AUTHOR]

The lab-on-a-chip concept, enabled by microfluidic technology, promises the integration of multiple discrete laboratory techniques into a miniaturised system. Research into microfluidics has generally focused on the development of individual elements of the total system (often with relatively limited functionality), without full consideration for integration into a complete fully optimised and miniaturised system. Typically, the operation of many of the reported lab-on-a-chip devices is dependent on the support of a laboratory framework. In this paper, a demonstrator platform for routine laboratory analysis is designed and built, which fully integrates a number of technologies into a single device with multiple domains such as fluidics, electronics, pneumatics, hydraulics, and photonics. This facilitates the delivery of breakthroughs in research, by incorporating all physical requirements into a single device. To highlight this proposed approach, this demonstrator microsystem acts as a fully integrated biochemical assay reaction system. The resulting design determines enzyme kinetics in an automated process and combines reservoirs, three-dimensional fluidic channels, optical sensing, and electronics in a low-cost, low-power and portable package. [ABSTRACT FROM AUTHOR]

There has been increasing interest in bacterial lipids in recent years due, in part, to their emerging role as molecular signalling molecules. Bacteroides thetaiotaomicron is an important member of the mammalian gut microbiota that has been shown to produce sphingolipids (SP) that pass through the gut epithelial barrier to impact host SP metabolism and signal into host inflammation pathways. B. thetaiotaomicron also produces a novel family of N-acyl amines (called glycine lipids) that are potent ligands of host Toll-like receptor 2 (TLR2). Here, we specifically examine the lipid signatures of four species of gut-associated Bacteroides. In total we identify 170 different lipids, and we report that the range and diversity of Bacteroides lipids is species specific. Multivariate analysis reveals that the differences in the lipid signatures are largely driven by the presence and absence of plasmalogens, glycerophosphoinositols and certain SP. Moreover, we show that, in B. thetaiotaomicron, mutations altering either SP or glycine lipid biosynthesis result in significant changes in the levels of other lipids, suggesting the existence of a compensatory mechanisms required to maintain the functionality of the bacterial membrane. [ABSTRACT FROM AUTHOR]

The Australian Curriculum: Mathematics encourages teachers to consider seriously the four proficiencies: Understanding, Fluency, Problem Solving and Reasoning. In responding to the reasoning proficiency, many teachers may find that the language of the classroom may well change. In this article, we discuss the meaning given to the term reasoning within the AC:M and elsewhere, share an example of a classroom task with the potential to develop mathematical reasoning, consider the language involved in describing reasoning, and present some survey responses on teachers' current understanding and use of the relevant terms. (Contains 3 tables, 2 figures and 1 footnote.)

At some stage in the planning process, teachers develop or select tasks which prompt the type of activity that can offer students experiences that can help them learn the intended content. This article presents results from an item on a survey that invited teachers to match particular content descriptions with selected tasks. While many teachers matched the tasks with the content descriptions that we anticipated they would, there were also many teachers who chose descriptions that we consider do not match the tasks. It is suggested that teachers should discuss within their planning teams the purpose and potential of particular tasks, and that such discussions also form part of teacher professional learning. It is recommended that the notion of matching tasks to the curriculum is incorporated into teacher learning sessions. (Contains 1 table.)

We are interested in exploring the processes teachers use when planning. We sought responses from teachers on aspects of their planning from a survey of various aspects of their decisions. We found that, while there is diversity in processes teachers use for planning, a consistent theme was that teachers make deliberative decisions at all stages in the planning process. Likewise teachers make active use of assessment information, especially to address the needs of their students. There are important implications from our findings for those who support teachers in the transition to the Australian Curriculum: Mathematics. (Contains 2 tables.)