Disproof of the Structures and Biosynthesis of Ergoynes, Gs-Polyyne-l-Ergothioneine Cycloadducts from Gynuella sunshinyii YC6258.

Some bacteria produce "bacterial polyynes" bearing a conjugated C≡C bond that starts with a terminal alkyne. Ergoynes A and B have been reported as sulfur-containing metabolites from Gynuella sunshinyii YC6258. These compounds were thought to be formed by cycloaddition between a bacterial polyyne (named Gs-polyyne) and l-ergothioneine. The biosynthetic gene clusters (BGCs), which may contribute to their synthesis, were present in the YC6258 genome. The biosynthetic origin of Gs-polyyne is interesting considering its rare 2-isopentyl fatty acyl skeleton. Here, the structures and biosynthesis of Gs-polyyne and ergoynes were verified by analytical, chemical, and genetic techniques. In the YC6258 extract, which was prepared considering their instability, Gs-polyyne was detected as a major LC peak, and ergoynes were not detected. The NMR data of the isolated Gs-polyyne contradicted the proposed structure and identified it as the previously reported protegenin A. The expression of Gs-polyyne BGC in Escherichia coli BL21(DE3) also yielded protegenin A. The cyclization between protegenin A and l-ergothioneine did not proceed during sample preparation; a base, such as potassium carbonate, was required. Overall, Gs-polyyne was identified as protegenin A, while ergoynes were determined to be artifacts. This cyclization may provide a derivatization to stabilize polyynes or create new chemical space.

RaptGen-Assisted Generation of an RNA/DNA Hybrid Aptamer against SARS-CoV-2 Spike Protein.

Optimization of aptamers in length and chemistry is crucial for industrial applications. Here, we developed aptamers against the SARS-CoV-2 spike protein and achieved optimization with a deep-learning-based algorithm, RaptGen. We conducted a primer-less SELEX against the receptor binding domain (RBD) of the spike with an RNA/DNA hybrid library, and the resulting sequences were subjected to RaptGen analysis. Based on the sequence profiling by RaptGen, a short truncation aptamer of 26 nucleotides was obtained and further optimized by a chemical modification of relevant nucleotides. The resulting aptamer is bound to RBD not only of SARS-CoV-2 wildtype but also of its variants, SARS-CoV-1, and Middle East respiratory syndrome coronavirus (MERS-CoV). We concluded that the RaptGen-assisted discovery is efficient for developing optimized aptamers.

Kinesiophobia, self-reported ankle function, and sex are associated with perceived ankle instability in college club sports athletes with chronic ankle instability.

OBJECTIVE: To investigate the association between sex, self-reported ankle function, pain intensity, kinesiophobia, and perceived ankle instability in athletes with chronic ankle instability (CAI). DESIGN: Cross-Sectional Study. SETTING: University. PARTICIPANTS: College club sports athletes with CAI (n = 42). MAIN OUTCOME MEASURES: Relationships with the Cumberland Ankle Instability Tool (CAIT) score and the Tampa Scale for Kinesiophobia-11 (TSK-11), the Foot and Ankle Ability Measure (FAAM), sex (0: male, 1: female), and ankle pain intensity by the Numeric Rating Scale were explored with multiple regression analysis. RESULTS: The regression model explained 50.3% of the variance of the CAIT score (P < 0.001), and the TSK-11 score (B = -0.382, P = 0.002), the FAAM sports subscale score (B = 0.122, P = 0.038), and sex (B = -2.646, P = 0.031) were significant independent variables for the CAIT score (P < 0.001), while pain intensity was not significant (B = -0.182, P = 0.504). These results indicated that higher TSK-11 score, lower FAAM sports subscale score, and being female were related to lower CAIT score. CONCLUSIONS: Kinesiophobia related to perceived instability along with self-reported function and sex in athletes with CAI. Clinicians should assess the psychological aspects of athletes with CAI.

Inertial Sensor-Based Assessment of Static Balance in Athletes with Chronic Ankle Instability.

The Balance Error Scoring System (BESS), a subjective examiner-based assessment, is often employed to assess postural balance in individuals with chronic ankle instability (CAI); however, inertial sensors may enhance the detection of balance deficits. This study aimed to compare the BESS results between the CAI and healthy groups using conventional BESS scores and inertial sensor data. The BESS test (six conditions: double-leg, single-leg, and tandem stances on firm and foam surfaces, respectively) was performed for the CAI (n = 16) and healthy control (n = 16) groups with inertial sensors mounted on the sacrum and anterior shank. The BESS score was calculated visually by the examiner by counting postural sway as an error based on the recorded video. The root mean square for resultant acceleration (RMSacc) in the anteroposterior, mediolateral, and vertical directions was calculated from each inertial sensor affixed to the sacral and shank surfaces during the BESS test. The mixed-effects analysis of variance and unpaired t-test were used to assess the effects of group and condition on the BESS scores and RMSacc. No significant between-group differences were found in the RMSacc of the sacral and shank surfaces, and the BESS scores (P > 0.05), except for the total BESS score in the foam condition (CAI: 14.4 ± 3.7, control: 11.7 ± 3.4; P = 0.039). Significant main effects of the conditions were found with respect to the BESS scores and RMSacc for the sacral and anterior shank (P < 0.05). The BESS test with inertial sensors can detect differences in the BESS conditions for athletes with CAI. However, our method could not detect any differences between the CAI and healthy groups.

Lower limb kinematics during single leg landing in three directions in individuals with chronic ankle instability.

OBJECTIVES: To compare the lower limb kinematics of participants with chronic ankle instability (CAI) and healthy participants during forward, lateral, and medial landings. DESIGN: Cross-sectional study. SETTING: Laboratory. PARTICIPANTS: Eighteen athletes with CAI and 18 control athletes. MAIN OUTCOME MEASURES: Hip, knee, and ankle joint kinematics during forward, lateral, and medial single-leg landings were compared between the groups using two-way ANOVA for discrete values and statistical parametric mapping two-sample t-tests for time-series data. RESULTS: The CAI group had significantly greater ankle dorsiflexion than the control group (P ≤ 0.013), which was observed from the pre-initial contact (IC) for lateral and medial landings and post-IC for forward landing. The CAI group showed greater knee flexion than the control group from the IC for lateral landing and post-IC for forward landing (P ≤ 0.014). No significant differences in ankle inversion kinematics were found between the CAI and control groups. Lateral landing had a greater peak inversion angle and velocity than forward and medial landings (P < 0.001). Medial landing had a greater inversion velocity than forward landing (P < 0.001). CONCLUSIONS: This study suggests that individuals with CAI show feedforward protective adaptations in the pre-landing phase for lateral and medial landings.

Cytoplasmic granule formation by FUS-R495X is attributable to arginine methylation in all Gly-rich, RGG1 and RGG2 domains.

Many mutations in the fused in sarcoma (FUS) gene have been identified as genetic causative factors of amyotrophic lateral sclerosis (ALS). As a certain number of mutants form aberrant cytoplasmic granules under specific conditions, granule forming ability of FUS is believed to be linked to the pathogenesis of ALS. However, molecular mechanisms underlying this property remain unclear. An ALS-linked FUS mutant, R495X, shows extensive cytoplasmic localization and forms granules in neurons. In the present study, using R495X domain deletion constructs, we showed that deletion of any of Gly-rich, RGG1 or RGG2 significantly suppressed granule formation. Furthermore, when neurons expressing EGFP-R495X were treated with an arginine methylation inhibitor, the number of cells displaying R495X granules was significantly reduced. When FLAG-tagged arginine N-methyltransferase 8 (PRMT8) was co-expressed with EGFP-R495X to facilitate its methylation, the number of cells with granules was significantly increased. Collectively, these findings suggest that cytoplasmic granule formation by R495X is attributable to the arginine methylation in all Gly-rich, RGG1 and RGG2 domains.