As an important material in pharmaceutical and chemical industry, β-alanine was mainly produced by chemical methods. L-aspartate-α-decarboxylase could catalyze the α-decarboxylation from L-aspartate to β-alanine. Determinations for specific activities of PanDs from Escherichia coli, Corynebacterium glutamicum and Bacillus subtilis were performed in this study (0.98 U/mg, 7.52 U/mg and 8.4 U/mg respectively). The optimal temperature and pH of PanDs from C. glutamicum and B. subtilis were 65 degrees C, pH 6.5 and 60 degrees C, pH 6.5 respectively. According to our research, PanD from B. subtilis could be more appropriate for industrial application because of the higher activity and thermostability when compared to PanDs from E. coli and C. glutamicum which had been the most studied. We also analyzed and discussed the special post-translation self-cleavage phenomenon and the mechanism based inactivation.
Bacillus subtilis ; enzymology ; Bacterial Proteins ; genetics ; metabolism ; Corynebacterium glutamicum ; enzymology ; Escherichia coli ; enzymology ; Glutamate Decarboxylase ; genetics ; metabolism ; Industrial Microbiology ; Temperature ; beta-Alanine

Objective To explore the clinical effect of manipulation treatment combined with auricular point sticking on vertebral artery cervical spondylopathy. Methods 120 patients with vertebral artery cervical spondylopathy were randomly divided into 3 groups, 40 cases in each. The comprehensive group received manipulation treatment and auricular point sticking. The manipulation treatment group received manipulation treatment only and the auricular point sticking group received auricular point sticking only. The peak systolic velocity (Vp), end diastolic peak flow velocity (Vd), mean peak flow velocity (Vm) of the vertebral-basilar artery were checked before and after treatment. Results The clinical cure rates (80%) was higher in the comprehensive group than in the manipulation treatment group (52.5%) and in the auricular point sticking group (47.5%) (P<0.01). The Vp, Vd, Vm in 3 groups improved obviously after treatment (P<0.05), especially in the comprehensive group (P<0.01). Conclusion Manipulation treatment with auricular point sticking is more effective on vertebral artery cervical spondylopathy than simply manipulation treatment or auricular point sticking.

Objective:To investigate the relationship between the virulence and the carbapenem resistance phenotype of Klebsiella pneumoniae from blood infection,and to identify carbapenem-resistant and hypervirulent Klebsiella pneumoniae(CR-HVKP)strains.Methods:A total of 192 Klebsiella pneumoniae strains were isolated from blood culture of patients with bloodstream infections from 2016 to 2019,of which 96 isolates were carbapenem-resistant Klebsiella pneumoniae(CRKP)and 96 were carbapenem-sensitive Klebsiella pneumoniae(CSKP).The drug susceptibility was detected by VITEK-2 automatic microbial analyzer;carbapenemase genes,virulence genes and capsule typing were detected by polymerase chain reaction;the high viscosity phenotype of strains was detected by string test,and the genome characteristics of CR-HVKP were detected by whole genome sequencing.Serum killing and biofilm formation test were used to further verify the virulence of CR-HVKP.Results:There were significant differences in drug resistance to common antibiotics,except for minocycline between CSKP and CRKP isolates(all P<0.05).92 out of 96 CRKP isolates carried carbapenemase genes,mainly blaKPC-2.The string tests were positive in 4 isolates of CRKP and 36 isolates of CSKP(P<0.05).The detection rates of virulence genes Kfu,aerobictin,iutA,ybtS,rmpA,magA,allS,and capsule antigen K1 and K2 in CSKP group were significantly higher than those in CRKP group(all P<0.05).One HVKP strain was detected in the CRKP group(CR-HVKP)and 36 HVKP was detected in the CSKP group(P<0.05).The CR-HVKP strain belonged to the MLST412,serotype K57,expressed iutA,entB,mrkD,fimH,and rmpA virulence genes,and showed strong biofilm formation and significantly increased serum resistance.Whole genome sequencing results showed that this CR-HVKP isolate carried blaSHV-145,blaTEM-1,blaCTX-M-3,fosA6,oqxA5,oqxB26,and aac(3)-Ⅱd resistance genes,accompanied by abnormalities in outer membrane protein K(OmpK)35 and OmpK36.Conclusions:The drug resistance of CRKP is significantly higher than that of CSKP,while CRKP carrying fewer virulence genes in both number and types compared to CSKP.A new MLST type of carbapenem-resistant and hypervirulent Klebsiella pneumoniae strain has been detected,which requires clinical awareness and epidemiological monitoring.

Objective: To explore the genetic basis for a pedigree affected with Marfan syndrome (MFS). Methods: Clinical data of the patients was collected.With genomic DNA extracted from peripheral blood samples, potential mutation was detected by targeted exome sequencing.Candidate variants were validated by Sanger sequencing and bioinformatic analysis. Results: Targeted exome sequencing and Sanger sequencing revealed a missense c. 649T>C(p.Trp217Arg) variant in the exon 7 of FBN1 gene, which was unreported previously.Bioinformatics analysis suggested that the variant can cause amino acid replacement and affect the structure and function of fibrillin-1. Conclusion A novel missense variant of the FBN1 gene was identified, which probably underlies the autosomal dominant MFS in this pedigree.