Engineering photo-methylotrophic Methylobacterium for enhanced 3-hydroxypropionic acid production during non-growth stage fermentation.

This study explored the potential of methanol as a sustainable feedstock for biomanufacturing, focusing on Methylobacterium extorquens, a well-established representative of methylotrophic cell factories. Despite this bacterium's long history, its untapped photosynthetic capabilities for production enhancement have remained unreported. Using genome-scale flux balance analysis, it was hypothesized that introducing photon fluxes could boost the yield of 3-hydroxypropionic acid (3-HP), an energy- and reducing equivalent-consuming chemicals. To realize this, M. extorquens was genetically modified by eliminating the negative regulator of photosynthesis, leading to improved ATP levels and metabolic activity in non-growth cells during a two-stage fermentation process. This modification resulted in a remarkable 3.0-fold increase in 3-HP titer and a 2.1-fold increase in its yield during stage (II). Transcriptomics revealed that enhanced light-driven methanol oxidation, NADH transhydrogenation, ATP generation, and fatty acid degradation were key factors. This development of photo-methylotrophy as a platform technology introduced novel opportunities for future production enhancements.

[A preliminary report of SARS coronavirus specific RNA in SARS convalescents and medical person].

OBJECTIVE: To observe the method of fluorescent-polymerase chain reaction (F-PCR) and gene-hip technique in detecting coronavirus in severe acute respiratory syndrome (SARS) and its value for clinical application. METHODS: Serum of 60 SARS patients, 20 samples of serum and 20 samples of gargling fluid of medical staff of the "Fever Clinic", and one cDNA specimen obtained from one SARS suspect patient were examined with F-PCR diagnosis kit and gene-chip technique for SARS coronavirus. RESULTS: Three methods, including DR Chip and two F-PCR kit from Zhongshan College Da'an gene stock company and Shanghai Fortune industrial joint-stock Co, Ltd, were used, and the results were all negative for all specimens, except one cDNA specimen, which was obtained from one SARS suspect patient, virus could be amplified by F-PCR. CONCLUSION: Special RNA fragment of SARS virus has not been detected in gargling fluid and serum of SARS convalescents and medical staff.

[Comparison of serum biochemical features between SARS and other viral pneumonias].

OBJECTIVE: To identify blood chemistry changes in coronavirus of severe acute respiratory syndrome (SARS). METHODS: Biochemical changes in SARS patients were summarized and compared with other viral pneumonias. Serum total protein (TP), albumin (Alb), total cholesterol (TC), triglyceride (TG), calcium (Ca), ferrum (Fe), lactate dehydrogenase (LDH), creatine kinase (CK), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) between SARS and other viral pneumonias were examined by Roche Diagnostics assay, HITACHI7600 automatic analyzer. Clinically confirmed SARS patients, patients with other viral pneumonias, and healthy controls were included in the study. RESULTS: Compared with healthy person, the levels of serum TC, Fe, Ca, Alb were significantly lowered (P<0.05 or P<0.01), while the activity of LDH, CK, ALT, AST were elevated, the increase of CK and the decrease of Fe were the most significant (P<0.05 or P<0.01), the changes of TP and TG were not obvious. In the other viral pneumonias patients, ALT, AST, LDH were elevated slightly than those of healthy person, while Fe, Ca, Alb, TC, CK were a little reduced, but there was no significant difference between the two groups. In convalescent stage, all the tests were returned to normal ranges except ALT, AST were still elevated in SARS patients. CONCLUSION: The changes in serum biochemistry are more marked in SARS patients compared with patients suffering from other viral pneumonias, the decrease of Fe as well as the inhibition of TC may be caused by the treatment of anti-virus.

[Studies of bi-derectional modulation effect of kudzuvine root on immunol cells].

OBJECTIVE: To evaluate bi-directional modulation effect of Chinese herbal medicine on immunol cells. METHOD: Two different active portions were isolated from Kudzuvine Root(Radix puerariae), one being the ethanol extraction and another the water extraction. Different concentration of these two different portions was studied by using PMA stimulated lymphocyte or eosinophil initiated chemiluminescence system. RESULT: Water extraction of Kudzuvine Root could enhance chemiluminescence concentration dependently whereas enthanol extraction of Kudzuvine Root inhibited the chemiluminescence significantly. CONCLUSION: The bi-directional regulation effect of Chinese herbal medicine can be found in the same herb, because of its efficacy of different active compounds.

[Anti-mutagenesis effects of total flavonoids of Astragalus].

OBJECTIVE: To investigate the anti-mutagenic action of the total flavonoids of Astragalus (TFA). METHOD: Three groups of concentrations of TFA and one inducer group were used. The anti-mutagenic action of TFA was studied by experiments in vitro and in vivo including miconucleolus assay, semen teraogenesis test and gene mutagenesis of V79/HGPRT. RESULT: TFA did not affect the weight of the mice during the experiment period. The high concentration of TFA could significantly reduce cyclohophamide-induced miconucleolus number and gene mutagenesis of V79/HGPRT compared with inducer group. However, TFA did not make statistic change in the semen teraogenesis induced by mitomycin C. CONCLUSION: TFA has antimutagenesis effect.