Pyrroquinoline quinone-dependent alcohol dehydrogenase (PQQ-ADH) is a key enzyme in the ethanol oxidase respiratory chain of acetic acid bacteria (AAB). To investigate the effect of PQQ-ADH on acetic acid production by Acetobacter pasteurianus JST-S, subunits I (adhA) and II (adhB) of PQQ-ADH were over-expressed, the fermentation parameters and the metabolic flux analysis were compared in the engineered strain and the original one. The acetic acid production was improved by the engineered strain (61.42 g L−1) while the residual ethanol content (4.18 g L−1) was decreased. Analysis of 2D maps indicated that 19 proteins were differently expressed between the two strains; of these, 17 were identified and analyzed by mass spectrometry and two-dimensional gel electrophoresis. With further investigation of metabolic flux analysis (MFA) of the pathway from ethanol and glucose, the results reveal that over-expression of PQQ-ADH is an effective way to improve the ethanol oxidation respiratory chain pathway and these can offer theoretical references for potential mechanism of metabolic regulation in AAB and researches with its acetic acid resistance.

This study investigated injury patterns and the use of computed tomography (CT) among Chinese children with mild traumatic brain injury (MTBI). We enrolled children with MTBI who were treated within 24 hours of head trauma in the emergency department of Wuhan Medical Care Center for Women and Children in Wuhan, China. Characteristics of MTBIs were analyzed by age and gender. Results of cranial CT scan and clinically-important brain injury (ciTBI) for children were obtained. The definition of ciTBI was: death from TBI, intubation for more than 24 h for TBI, neurosurgery, or hospital admission of 2 nights or more. Of 455 eligible patients with MTBI, ciTBI occurred in two, and no one underwent neurosurgical intervention. CT scans were performed for 441 TBI patients (96.9%), and abnormal findings were reported for 147 patients (33.3%, 95% CI 29.0–37.8). Falls were the leading cause of MTBI (61.5%), followed by blows (18.9%) and traffic collisions (14.1%) for children in the 0–2 group and 10–14 group. For children aged between 3 and 9, the top three causes of TBI were falls, traffic collisions and blows. Leisure activity was the most reported activity when injuries occurred for all age groups. Sleeping/resting and walking ranked in the second and third place for children between 0 and 2 years of age, and walking and riding for the other two groups. The places where the majority injuries occurred were the home for the 0–2 and 3–9 years of age groups, and school for the 10–14 years of age group. There was no statistical difference between boys and girls with regard to the activity that caused the MTBI. This study highlights the important roles that parents and school administrators in the development of preventive measures to reduce the risk of traumatic brain injury in children. Also, identifying children who had a head trauma at very low risk of clinically important TBI for whom CT might be unnecessary is a priority area of research in China.

JST-S was screened from solid fermented grains of vinegar in China, identified by molecular analysis, and used for the production of purple sweet potato vinegar using purple sweet potato as the substrate. By orthogonal experiment, maximum total acid concentration (4.26% [v/v]) was achieved under optimized conditions as follows: fermentation time, 3.5 days; ethanol content, 9% v/v; and inoculum size, 8% v/v. During the production of purple potato vinegar, the anthocyanin concentration decreased from 652.07 to 301.73 μg/mL. The antioxidant activity of products, including diphenyl-picryl hydrazide radical-scavenging capacity (above 60%), reducing power (above 0.47), and hydroxyl radical-scavenging capacity (above 46%), showed positive linear regression ( < 0.01), which could be related with the changes in anthocyanin concentration and antioxidant activities at different stages of vinegar fermentation. The acetic acid and other non-phenolic antioxidants in purple sweet potato vinegar may have contributed to the antioxidant activities. Results of these studies may provide a reference for the industrial production of vinegar by liquid fermentation of purple sweet potato.

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