ABSTRACT
As an important platform compound, 3-hydroxypropionic acid (3-HP) can be used as a substrate to synthesize a variety of biological products with commercial potential. The titer of 3-HP by wild-type bacteria is low, which severely limits the large-scale application and production of 3-HP. By modifying the genes related to the metabolic pathway, engineered bacteria using cheap substrates as carbon sources are constructed, the aim of reducing production cost and increasing output is realized. In this paper, the recent progress in the synthesis of 3-HP by metabolic engineering at home and abroad is reviewed. The advantages and disadvantages of glycerol pathway, malonyl-CoA pathway and beta-alanine pathway for synthesis of 3-HP are also summarized and analyzed, and the future development of 3-HP is prospected.
Subject(s)
Glycerol , Metabolism , Industrial Microbiology , Lactic Acid , Metabolic Engineering , Metabolic Networks and Pathways , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To detect the presence of ROS1 fusion gene in pulmonary adenocarcinoma and its clinicopathologic parameters.</p><p><b>METHODS</b>Fluorescence RT-PCR was used to detect the presence of ROS1 fusion gene in 369 surgical resection samples of pulmonary adenocarcinoma with known EGFR mutation status. The presence of ROS1 fusion gene in correlation with clinicopathologic features was analyzed. Sixteen positive and 20 negative samples by RT-PCR were further confirmed by direct sequencing.</p><p><b>RESULTS</b>ROS1 fusion gene was detected in 16 of 369 lung adenocarcinoma samples (4.3%). The presence of ROS1 fusion gene was not correlated to gender, age, smoking history, tumor site, size, histological subtype, tumor differentiation, T staging, lymph node metastasis, TNM staging and EGFR mutation (P > 0.05). The frequency of ROS1 fusion gene was similar in female and male patients, 4.4% (8/183) vs 4.3% (8/186), P > 0.05. The presence of ROS1 fusion gene in patients of ≤ 60 years of age was higher than that in patients of > 60 years, 5.1% (10/195) vs 3.4% (6/174), P > 0.05. The rate of ROS1 fusion gene of non-smokers was a slight higher than that of smokers, 4.4% (14/318) vs 3.9% (2/51), P > 0.05. Both positive and negative cases were confirmed by direct sequencing in all cases.</p><p><b>CONCLUSIONS</b>ROS1 fusion gene occurs more frequently in younger and non-smoking patients of pulmonary adenocarcinoma, and may coexist with EGFR mutations. ROS1 fusion gene seems to define a distinct subset of pulmonary adenocarcinoma.</p>
ABSTRACT
AIM:To investigate the expression of C/EBP homologous protein (CHOP) and its correlation with proliferative/apoptotic ratio (PAR) in colorectal adenoma-carcinoma sequence under the same genetic background .ME-THODS:Four kinds of tissue samples under the same genetic background from 23 patients, including normal colorectal tissue, adenoma with low-grade intraepithelial neoplasia , adenoma with high-grade intraepithelial neoplasia and colorectal adenocarcinoma samples , were collected .TUNEL method and Ki-67 immunohistochemistry were applied to determine the PAR.The expression of CHOP was detected by immunohistochemistry SABC method .RESULTS: ( 1 ) Under the same genetic background , the level of CHOP expression is significantly higher in colorectal adenocarcinoma than that in the ade -noma with high-grade intraepithelial neoplasia , the adenoma with low-grade intraepithelial neoplasia and the normal muco-sa.The level of CHOP expression was significantly higher in the adenoma with high -grade intraepithelial neoplasia than that in the adenoma with low-grade intraepithelial neoplasia and the normal mucosa .The level of CHOP expression was signifi-cantly higher in the adenoma with low-grade intraepithelial neoplasia than that in normal mucosa .(2) Under the same ge-netic background , PAR was significantly higher in the colorectal adenocarcinoma than that in the adenoma with high -grade intraepithelial neoplasia , the adenoma with low-grade intraepithelial neoplasia and the normal mucosa .PAR was significant-ly higher in the adenoma with high-grade intraepithelial neoplasia than that in the adenoma with low-grade intraepithelial neoplasia and the normal mucosa .PAR was significantly higher in the adenoma with low-grade intraepithelial neoplasia than that in the normal mucosa.(3) CHOP levels were positively correlated with PAR in the adenoma with low-grade intraepi-thelial neoplasia , adenoma with high-grade intraepithelial neoplasia and colorectal adenocarcinoma .CONCLUSION:CHOP expression and PAR continuously increased and positively correlated along the adenoma -carcinoma sequence , indica-ting that endoplasmic reticulum stress mediates the carcinogenesis of colorectal adenomas .