1.Transformation of phosphotransferase system in Escherichia coli.
Mengrong XIAO ; Liang ZHANG ; Shuangping LIU ; Guiyang SHI
Chinese Journal of Biotechnology 2014;30(10):1561-1572
We constructed several recombinant Escherichia coli strains to transform phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS system) and compared the characteristics of growth and metabolism of the mutants. We knocked-out the key genes ptsI and ptsG in PTS system by using Red homologous recombination in E. coli and meanwhile we also knocked-in the glucose facilitator gene glf from Zymomonas mobilis in the E. coli chromosome. Recombinant E. coli strains were constructed and the effects of cell growth, glucose consumption and acetic acid accumulation were also evaluated in all recombinant strains. The deletion of gene ptsG and ptsI inactivated some PTS system functions and inhibited the growth ability of the cell. Expressing the gene glf can help recombinant E. coli strains re-absorb the glucose through Glf-Glk (glucose facilitator-glucokinase) pathway as it can use ATP to phosphorylate glucose and transport into cell. This pathway can improve the availability of glucose and also reduce the accumulation of acetic acid; it can also broaden the carbon flux in the metabolism pathway.
Biological Transport
;
Escherichia coli
;
enzymology
;
genetics
;
Gene Deletion
;
Gene Knock-In Techniques
;
Gene Knockout Techniques
;
Glucose
;
metabolism
;
Phosphoenolpyruvate Sugar Phosphotransferase System
;
genetics
;
Zymomonas
;
genetics
2.Analysis of factors associated with infection and death of carbapenem-resistant Klebsiellapneumoniae
Xiao WANG ; Yihai GU ; Wei ZHANG ; Yan JIANG ; Minghui DENG ; Xuan HOU ; Mengrong ZHOU ; Hui WANG ; Xiaobo LI
Chinese Journal of Preventive Medicine 2024;58(4):545-551
To analyze the factors associated with infection and death of carbapenem-resistant Klebsiella pneumoniae (CRKP) in patients. Using a case-control study method, patients with CRKP infection from January 2019 to December 2021 in the 3201 Hospital were selected as the case group, and patients with carbapenem-susceptible Klebsiella pneumoniae (CSKP) infection in the same period were selected as the control group in a ratio of 1∶1. The study subjects were followed up for 30 days. The two groups of patients were categorized into survival and death groups based on whether they died or not, respectively, and the 30-day morbidity and mortality rates of the CRKP case group and the CSKP control group were compared. The logistic regression model was used to analyze the factors associated with CRKP infection and death after CRKP infection. This study included 59 cases in the CRKP case group and 59 in the CSKP control group. The 30-day mortality rate of CRKP-infected patients and CSKP-infected patients were 30.5% (18/59) and 5.1% (3/59), with statistically significant differences ( P<0.001). Surgery within three months prior to KP infection ( OR=17.285, P=0.001), use of carbapenems within three months prior to KP infection ( OR=11.235, P=0.002), use of more than three types of antibiotics ( OR=7.993, P=0.016), albumin<30 g/L in patients prior to KP infection ( OR=10.463, P=0.002), sex ( OR=0.078, P<0.001), and diabetes ( OR=0.076, P=0.011) were associated factors of CRKP infection. Higher age-corrected Charlson Comorbidity Index scores of patients ( OR=1.522, P=0.024) and use of carbapenems by the patients with in the first three months prior to the KP infection ( OR=4.902, P=0.029) were associated factors for the deaths of patients with CRKP. In conclusion, medical personnel should be cautious in performing invasive procedures, strictly control the use of antibiotics, and provide targeted protection and treatment for high-risk patients as soon as possible.
3.Analysis of factors associated with infection and death of carbapenem-resistant Klebsiellapneumoniae
Xiao WANG ; Yihai GU ; Wei ZHANG ; Yan JIANG ; Minghui DENG ; Xuan HOU ; Mengrong ZHOU ; Hui WANG ; Xiaobo LI
Chinese Journal of Preventive Medicine 2024;58(4):545-551
To analyze the factors associated with infection and death of carbapenem-resistant Klebsiella pneumoniae (CRKP) in patients. Using a case-control study method, patients with CRKP infection from January 2019 to December 2021 in the 3201 Hospital were selected as the case group, and patients with carbapenem-susceptible Klebsiella pneumoniae (CSKP) infection in the same period were selected as the control group in a ratio of 1∶1. The study subjects were followed up for 30 days. The two groups of patients were categorized into survival and death groups based on whether they died or not, respectively, and the 30-day morbidity and mortality rates of the CRKP case group and the CSKP control group were compared. The logistic regression model was used to analyze the factors associated with CRKP infection and death after CRKP infection. This study included 59 cases in the CRKP case group and 59 in the CSKP control group. The 30-day mortality rate of CRKP-infected patients and CSKP-infected patients were 30.5% (18/59) and 5.1% (3/59), with statistically significant differences ( P<0.001). Surgery within three months prior to KP infection ( OR=17.285, P=0.001), use of carbapenems within three months prior to KP infection ( OR=11.235, P=0.002), use of more than three types of antibiotics ( OR=7.993, P=0.016), albumin<30 g/L in patients prior to KP infection ( OR=10.463, P=0.002), sex ( OR=0.078, P<0.001), and diabetes ( OR=0.076, P=0.011) were associated factors of CRKP infection. Higher age-corrected Charlson Comorbidity Index scores of patients ( OR=1.522, P=0.024) and use of carbapenems by the patients with in the first three months prior to the KP infection ( OR=4.902, P=0.029) were associated factors for the deaths of patients with CRKP. In conclusion, medical personnel should be cautious in performing invasive procedures, strictly control the use of antibiotics, and provide targeted protection and treatment for high-risk patients as soon as possible.