Engineering Rhodosporidium toruloides for production of 3-hydroxypropionic acid from lignocellulosic hydrolysate.

Microbial production of valuable bioproducts is a promising route towards green and sustainable manufacturing. The oleaginous yeast, Rhodosporidium toruloides, has emerged as an attractive host for the production of biofuels and bioproducts from lignocellulosic hydrolysates. 3-hydroxypropionic acid (3HP) is an attractive platform molecule that can be used to produce a wide range of commodity chemicals. This study focuses on establishing and optimizing the production of 3HP in R. toruloides. As R. toruloides naturally has a high metabolic flux towards malonyl-CoA, we exploited this pathway to produce 3HP. Upon finding the yeast capable of catabolizing 3HP, we then implemented functional genomics and metabolomic analysis to identify the catabolic pathways. Deletion of a putative malonate semialdehyde dehydrogenase gene encoding an oxidative 3HP pathway was found to significantly reduce 3HP degradation. We further explored monocarboxylate transporters to promote 3HP transport and identified a novel 3HP transporter in Aspergillus pseudoterreus by RNA-seq and proteomics. Combining these engineering efforts with media optimization in a fed-batch fermentation resulted in 45.4 g/L 3HP production. This represents one of the highest 3HP titers reported in yeast from lignocellulosic feedstocks. This work establishes R. toruloides as a host for 3HP production from lignocellulosic hydrolysate at high titers, and paves the way for further strain and process optimization towards enabling industrial production of 3HP in the future.

Enhanced percutaneous delivery of recombinant human epidermal growth factor employing nano-liposome system.

We encapsulated recombinant human epidermal growth factor (rhEGF) into nano-liposomes (NLs) system for topical delivery. The rhEGF-loaded NLs were prepared using a high pressure homogenization method. Morphology and overall particle distribution of NLs were investigated using transmission electron microscopy (TEM) and high resolution microscope (CytoViva™). Particle size, zeta (ζ) potential and encapsulation efficiency were measured and the percutaneous delivery of NLs was evaluated using Franz diffusion cells and immunofluorescence confocal laser scanning microscopy (CLSM). The mean particle size, zeta potential and encapsulation efficiency of the NLs were 155.57 ± 2.59 nm, -57.92 ± 4.35 mV and 9.00 ± 0.39%, respectively. TEM and microscopic analysis showed spherical, very even-sized vesicles approximately 150 nm. The skin permeation and localization of rhEGF were enhanced by NLs. CLSM image analysis provided that the NLs enhanced the permeation and localization of rhEGF in rat skin by facilitating entry through pores of skin.

Associations Between Periodontitis and Chronic Obstructive Pulmonary Disease: The 2010 to 2012 Korean National Health and Nutrition Examination Survey.

BACKGROUND: The aim of this study is to examine whether oral hygiene and self-care, particularly in periodontal health, are associated with chronic obstructive pulmonary disease (COPD) in the Korean population. METHODS: Data from the Korean National Health and Nutrition Examination Survey from 2010 to 2012 were used to assess the community periodontal index (CPI) of 5,878 participants (normal lung function: n = 5,181; obstructive spirometric pattern: n = 697) aged ≥40 years, who underwent spirometry. RESULTS: Participants with COPD brushed their teeth less frequently and used the following less frequently: 1) dental floss and/or interdental brush; 2) mouthwash; and 3) electric toothbrush (P <0.001). Prevalence of periodontitis in patients with COPD (58.1%) was significantly higher than in those without COPD (34.0%, P <0.001). Number of teeth was significantly lower in patients with COPD compared with controls. Decayed-missing-filled tooth index was significantly lower in patients with COPD. This study shows risk of COPD by periodontal severity. Periodontitis (CPI 3 and 4) was associated in males with COPD after adjustment for: 1) age; 2) income; 3) education; 4) smoking; 5) alcohol consumption; 6) exercise; 7) body mass index; 8) toothbrushing frequency; 9) diabetes mellitus; and 10) number of teeth (CPI 3: relative risk [RR] = 1.38, 95% confidence interval [CI] = 1.12 to 2.05; CPI 4: RR = 1.23, 95% CI = 1.06 to 1.56). CONCLUSION: Findings of this cross-sectional study suggest that COPD in males may be associated with severe periodontitis and indicates the importance of promoting dental care in patients with COPD.