Porcine enzootic pneumonia is a chronic respiratory disease that affects swine. The etiological agent of the disease, Mycoplasma hyopneumoniae, is a bacterium that adheres to cilia of the swine respiratory tract, resulting in loss of cilia and epithelial cell damage. A M. hyopneumoniae protein P116, encoded by mhp108, was investigated as a potential adhesin. Examination of P116 expression using proteomic analyses observed P116 as a full-length protein and also as fragments, ranging from 17 to 70 kDa in size. A variety of pathogenic bacterial species have been shown to bind the extracellular matrix component fibronectin as an adherence mechanism. M. hyopneumoniae cells were found to bind fibronectin in a dose-dependent and saturable manner. Surface plasmon resonance was used to show that a recombinant C-terminal domain of P116 bound fibronectin at physiologically relevant concentrations (K D 24 ؎ 6 nM). Plasmin(ogen)-binding proteins are also expressed by many bacterial pathogens, facilitating extracellular matrix degradation. M. hyopneumoniae cells were found to also bind plasminogen in a dose-dependent and saturable manner; the C-terminal domain of P116 binds to plasminogen (K D 44 ؎ 5 nM). Plasminogen binding was abolished when the C-terminal lysine of P116 was deleted, implicating this residue as part of the plasminogen binding site. P116 fragments adhere to the PK15 porcine kidney epithelial-like cell line and swine respiratory cilia. Collectively these data suggest that P116 is an important adhesin and virulence factor of M. hyopneumoniae.

P97 and P102 paralogues occur as endoproteolytic cleavage fragments on the surface of Mycoplasma hyopneumoniae that bind glycosaminoglycans, plasminogen, and fibronectin and perform essential roles in colonization of ciliated epithelia. We show that the P102 paralogue Mhp384 is efficiently cleaved at an S/T-X-F↓X-D/E-like site, creating P60(384) and P50(384). The P97 paralogue Mhp385 is inefficiently cleaved, with tryptic peptides from a 115 kDa protein (P115(385)) and 88 kDa (P88(385)) and 27 kDa (P27(385)) cleavage fragments identified by LC-MS/MS. This is the first time a preprotein belonging to the P97 and P102 paralogue families has been identified by mass spectrometry. The semitryptic peptide (752)IQFELEPISLNV(763) denotes the C-terminus of P88(385) and defines the novel cleavage site (761)L-N-V↓A-V-S(766) in Mhp385. P115(385), P88(385), P27(385), P60(384), and P50(384) were shown to reside extracellularly, though it is unknown how the fragments remain attached to the cell surface. Heparin- and cilium-binding sites were identified within P60(384), P50(384), and P88(385). No primary function was attributed to P27(385); however, this molecule contains four tandem R1 repeats with similarity to porcine collagen type VI (α3 chain). P97 and P102 paralogue families are adhesins targeted by several proteases with different cleavage efficiencies, and this process generates combinatorial complexity on the surface of M. hyopneumoniae.

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Teacher and student perceptions of using technology enhanced learning (TEL) in higher education have received growing attention, particularly during COVID-19, however existing studies are mainly disciplinespecific. This study adopts a holistic cross-disciplinary approach. It compares teacher and student perceptions on defining TEL, promotors and barriers for its use, and solutions offered for better use of TEL in the future. Both qualitative and quantitative data were collected from an Australian university. A total of 75 teachers and 48 students completed an online survey, and of these participants, 24 teachers and 29 students participated in follow-up focus group interviews that included Kahoot! surveys. Quantitative results show that teacher and student perceptions on TEL were generally aligned except that self-reported technology savviness and confidence was rated higher than how students and staff rated each other. Qualitative analyses reveal that both teachers and students identified the main promoters for TEL as being: modern and expected in higher education, while being equalising, efficient, engaging, authentic, collaborative and flexible. The common barriers for using TEL were identified as fear, time, organisational culture, knowledge and technical/support issues, along with the perceived pitfalls of distraction, and superficial student learning. Solutions offered for TEL in the future from staff focused on the institution and a desire for strategic, pedagogical and holistic approaches, while students focussed on the accessibility, flexibility and collaborative potential of TEL. This cross-discipline pre-COVID-19 study of TEL perceptions offered by teachers and students has contributed to knowledge in this area by identifying barriers and solutions for TEL common to all disciplines that have the potential to be applied to whole of institution strategic approaches for the more effective use of TEL in teaching and learning in higher education. Student accessibility to TEL and the development of pedagogically sound digital learning resources bringing together educational developers and discipline experts are of particular relevance during and post-COVID-19.

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