Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Patient Prefer Adherence ; 17: 2421-2431, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808275

RESUMO

Background: It is important for anesthesiologists to leave good impressions and build rapport with patients during preoperative visits. However, patient preferences for anesthesiologist attire have not been well studied in China. Purpose: To characterize patient perceptions of anesthesiologist attire during preoperative visits. Patients and Methods: In this cross-sectional survey, we included adult patients who underwent elective operations in various surgical departments. We presented photographs of both male and female models wearing six combinations of attire (formal in a white coat buttoned, formal in a white coat unbuttoned, casual in a white coat buttoned, casual in a white coat unbuttoned, scrubs in a white coat buttoned, and scrubs in a coat of the same green color buttoned) in a randomized sequence. Participants were asked to rate each attire combination in five domains, including professionalism, experience, attitude, approachability, and caring. Results: Of the 541 surveys distributed, 516 (95.4%) were completed and included in the analysis. The majority of respondents were female [389 (75.4%)] and aged 31-45 years [234 (45.3%)]. The combination of scrubs in a buttoned coat of the same color had the highest composite rating score [median (interquartile range): 50 (45, 50), adjusted P<0.001 compared with the other five combinations]. There was no significant difference in preference for standardized disposable or personalized cloth operating caps. Respondents' age was independently associated with the perceived importance of anesthesiologist attire (46-60 years vs 18-35 years: odds ratio 2.17, 95% confidence interval 1.12-4.18, P=0.021). Conclusion: Patients prefer anesthesiologists wearing scrubs in coats of the same color. Standardizing anesthesiologist attire based on these findings may improve patient satisfaction.

2.
Nat Aging ; 3(4): 436-449, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37117794

RESUMO

Centenarians are an excellent model to study the relationship between the gut microbiome and longevity. To characterize the gut microbiome signatures of aging, we conducted a cross-sectional investigation of 1,575 individuals (20-117 years) from Guangxi province of China, including 297 centenarians (n = 45 with longitudinal sampling). Compared to their old adult counterparts, centenarians displayed youth-associated features in the gut microbiome characterized by an over-representation of a Bacteroides-dominated enterotype, increase in species evenness, enrichment of potentially beneficial Bacteroidetes and depletion of potential pathobionts. Health status stratification in older individuals did not alter the directional trends for these signature comparisons but revealed more apparent associations in less healthy individuals. Importantly, longitudinal analysis of centenarians across a 1.5-year period indicated that the youth-associated gut microbial signatures were enhanced with regard to increased evenness, reduction in interindividual variation and stability of Bacteroides, and that centenarians with low microbial evenness were prone to large microbiome instability during aging. These results together highlight a youth-related aging pattern of the gut microbiome for long-lived individuals.


Assuntos
Microbioma Gastrointestinal , Humanos , Adulto , Idoso de 80 Anos ou mais , Adolescente , Idoso , Microbioma Gastrointestinal/genética , Centenários , Estudos Transversais , China , Longevidade
3.
Mult Scler Relat Disord ; 68: 104213, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36223704

RESUMO

BACKGROUND: Neuropathic pain in neuromyelitis optica spectrum disorder (NMOSD) is common but has always been overlooked. This study was conducted to explore factors correlated with neuropathic pain in NMOSD and to evaluate associations between pain and quality of life. METHODS: In this cross-sectional study, NMOSD patients were interviewed face-to-face. The Brief Pain Inventory, Douleur Neuropathique 4, and Neuropathic Pain Symptom Inventory scales were used to evaluate pain. Patients completed the Beck Depression Inventory-II and Social Functioning-36 tests to evaluate depression and quality of life. RESULTS: A total of 122 NMOSD patients were enrolled. Eighty-one (66.4%; 95% CI, 39.9% to 92.9%) had current pain, of which 35 (28.7%; 95% CI, 20.7% to 36.7%) had neuropathic pain. Forty-nine (40.2%; 95% CI, 31.5% to 48.9%) patients experienced depression, which was moderate to severe in 22 patients. Multinomial logistic regression showed that significantly more patients with neuropathic pain had depression than those with other pain (OR, 4.15; 95% CI, 1.40 to 12.35; P=0.010) or no pain (OR, 5.65; 95% CI, 1.74 to 18.18; P=0.004). Significantly more patients with neuropathic pain had initial spinal cord involvement than those in the no-pain group (OR, 15.78; 95% CI, 1.37 to 182.15; P=0.027). Quality of life was severely affected in NMOSD patients with neuropathic pain. Only 29.6% were treated with analgesics, and none were prescribed antidepressants. CONCLUSION: Depression was correlated with neuropathic pain and was often overlooked. Initial spinal cord involvement might indicate a higher risk for neuropathic pain. Neuropathic pain in NMOSD patients requires scrutiny.


Assuntos
Neuralgia , Neuromielite Óptica , Humanos , Neuromielite Óptica/complicações , Neuromielite Óptica/epidemiologia , Qualidade de Vida , Estudos Transversais , Neuralgia/epidemiologia , Neuralgia/etiologia
4.
Appl Microbiol Biotechnol ; 106(9-10): 3691-3705, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35476152

RESUMO

spt23 plays multiple roles in the thermal tolerance of budding yeast. spt23 regulates unsaturated lipid acid (ULA) content in the cell, which can then significantly affect cellular thermal tolerance. Being a Ty suppressor, spt23 can also interact with transposons (Tys) that are contributors to yeast's adaptive evolution. Nevertheless, few studies have investigated whether and how much spt23 can exert its regulatory functions through transposons. In this study, expression quantitative trait loci (eQTL) analysis was conducted with thermal-tolerant Saccharomyces cerevisiae strains, and spt23 was identified as one of the most important genes in mutants. spt23-overexpression (OE), deletion (Del), and integrative-expressed (IE) strains were constructed. Their heat tolerance, ethanol production, the expression level of key genes, and lipid acid contents in the cell membranes were measured. Furthermore, LTR (long terminal repeat)-amplicon sequencing was used to profile yeast transposon activities in the treatments. The results showed the Del type had a higher survival rate, biomass, and ethanol production, revealing negative correlations between spt23 expression levels and thermal tolerance. Total unsaturated lipid acid (TULA) contents in cell membranes were lower in the Del type, indicating its negative association with spt23 expression levels. The Del type resulted in the lower richness and higher evenness in LTR distributions, as well as higher transposon activities. The intersection of 3 gene sets and regression analysis revealed the relative weight of spt23's direct and TY-induced influence is about 4:3. These results suggested a heat tolerance model in which spt23 increases cell thermal tolerance through transcriptional regulation in addition to spt23-transposon triggered unknown responses. KEY POINTS: • spt23 is a key gene for heat tolerance, important for LA contents but not vital. • Deletion of spt23 decreases in yeast's LTR richness but not in evenness. • The relative weight of spt23's direct and TY-induced influence is about 4:3.


Assuntos
Proteínas de Membrana , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Fatores de Transcrição , Etanol , Lipídeos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(6): 1023-1027, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36621792

RESUMO

Objective To investigate the incidence,treatment,therapeutic effect,and impact on quality of life of pain-depression comorbidity in the patients with neuromyelitis optica spectrum disorder(NMOSD).Methods The NMOSD patients comorbid with pain visiting the out-patient clinic of Peking Union Medical College Hospital were interviewed in a face-to-face manner by neurologists for evaluating the neurologic disease.Pain,depression,and quality of life were evaluated by anesthesiologists based on the brief pain inventory,the Beck depression inventory-Ⅱ,and the MOS 36-item short form health survey scales,respectively.Results Totally 81 patients were included in this study,among which 38(46.9%)patients comorbid with depression were enrolled in the comorbidity group.The pain severity showed no significant difference between the two groups(3.3±3.1 vs. 2.3±2.2,P=0.087).The daily life activities and health-related quality of life were more severely influenced in the patients with comorbidity than in the patients without comorbidity as illustrated by the breif pain inventory[general activity and normal work(P=0.001);mood,relationship with other people,and enjoyment of life(all P<0.001);walking ability(P=0.004);sleep(P=0.016)]and the MOS 36-item short form health survey scales[physical functioning(P=0.001);role-physical,bodily pain,general health,vitality,social functioning,role-emotional,mental health(all P<0.001)].Only 30.9% of pain sufferers received analgesic medications,with the mean pain reduction percentage of(53.6±28.9)%.None of the patients in this study took antidepressants.Conclusions Pain-depression comorbidity was common in NMOSD patients and severely influenced the quality of life of the patients.However,only a few patients received analgesic or antidepressant medications.Pain-depression comorbidity in NMOSD patients should be scrutinized.


Assuntos
Neuromielite Óptica , Humanos , Neuromielite Óptica/complicações , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/psicologia , Qualidade de Vida/psicologia , Depressão/epidemiologia , Comorbidade , Dor/epidemiologia
6.
Chin Med Sci J ; 37(4): 287-292, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36647590

RESUMO

Objective Airway-related patient safety incident (PSI) has always been the top concern of anesthesiologists because this type of incidents could severely threaten patient safety if not treated immediately and properly. This study intends to reveal the composition, prognosis, and to identify risk factors for airway related incidents reported by anesthesiologists. Methods All airway related PSIs reported by anesthesiologists in a Chinese academic hospital between September 2009 and May 2022 were collected from the PSI reporting system. Patients with airway incidents reported were matched 1:1 with controls based on sex and type of surgery. Univariable and multivariable analysis were performed to find risk factors associated with airway incident occurrence, and to evaluate influence of airway PSIs on patient prognosis. Results Among 1,038 PSIs voluntarily reported by anesthesiologists during the study period, 281 cases (27.1%) were airway-related incidents, with an overall reporting incidence of 4.74 per 10,000 among 592,884 anesthesia care episodes. Only ASA physical status was found to be significant independent predictor of these airway PSIs (P = 0.020). Patients with airway PSIs reported had longer extubation time (0.72 ± 1.56 d vs. 0.16 ± 0.77 d, 95%CI: 0.29 to 0.82, P < 0.001), longer ICU length of stay (LOS) (1.63 ± 5.71 d vs. 0.19 ± 0.84 d, 95%CI: 0.57 to 2.32, P= 0.001), longer post operative LOS (10.56 ± 13.09 d vs. 7.59 ± 10.76 d, 95%CI: 0.41 to 5.53, P = 0.023), and longer total in-hospital LOS (14.99 ± 15.18 d vs. 11.62 ± 11.88 d, 95%CI: 0.46 to 6.27,P = 0.024). Conclusions This single-center retrospective case-control study describes the composition of airway-related PSIs reported by anesthesiologists within thirteen years. Airway incidents might influence patient prognosis by elongating extubation time and LOS. Airway PSI data were worth analyzing to improve patient safety.


Assuntos
Anestesia , Segurança do Paciente , Humanos , Estudos Retrospectivos , Estudos de Casos e Controles , Anestesia/efeitos adversos , Fatores de Risco
7.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-970697

RESUMO

Objective Airway-related patient safety incident (PSI) has always been the top concern of anesthesiologists because this type of incidents could severely threaten patient safety if not treated immediately and properly. This study intends to reveal the composition, prognosis, and to identify risk factors for airway related incidents reported by anesthesiologists. Methods All airway related PSIs reported by anesthesiologists in a Chinese academic hospital between September 2009 and May 2022 were collected from the PSI reporting system. Patients with airway incidents reported were matched 1:1 with controls based on sex and type of surgery. Univariable and multivariable analysis were performed to find risk factors associated with airway incident occurrence, and to evaluate influence of airway PSIs on patient prognosis. Results Among 1,038 PSIs voluntarily reported by anesthesiologists during the study period, 281 cases (27.1%) were airway-related incidents, with an overall reporting incidence of 4.74 per 10,000 among 592,884 anesthesia care episodes. Only ASA physical status was found to be significant independent predictor of these airway PSIs (P = 0.020). Patients with airway PSIs reported had longer extubation time (0.72 ± 1.56 d vs. 0.16 ± 0.77 d, 95%CI: 0.29 to 0.82, P < 0.001), longer ICU length of stay (LOS) (1.63 ± 5.71 d vs. 0.19 ± 0.84 d, 95%CI: 0.57 to 2.32, P= 0.001), longer post operative LOS (10.56 ± 13.09 d vs. 7.59 ± 10.76 d, 95%CI: 0.41 to 5.53, P = 0.023), and longer total in-hospital LOS (14.99 ± 15.18 d vs. 11.62 ± 11.88 d, 95%CI: 0.46 to 6.27,P = 0.024). Conclusions This single-center retrospective case-control study describes the composition of airway-related PSIs reported by anesthesiologists within thirteen years. Airway incidents might influence patient prognosis by elongating extubation time and LOS. Airway PSI data were worth analyzing to improve patient safety.


Assuntos
Humanos , Segurança do Paciente , Estudos Retrospectivos , Estudos de Casos e Controles , Anestesia/efeitos adversos , Fatores de Risco
8.
Microbiol Spectr ; 9(1): e0008821, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34346754

RESUMO

Mbp1p is a component of MBF (MluI cell cycle box binding factor, Mbp1p-Swi6p) and is well known to regulate the G1-S transition of the cell cycle. However, few studies have provided clues regarding its role in fermentation. This work aimed to recognize the function of the MBP1 gene in ethanol fermentation in a wild-type industrial Saccharomyces cerevisiae strain. MBP1 deletion caused an obvious decrease in the final ethanol concentration under oxygen-limited (without agitation), but not under aerobic, conditions (130 rpm). Furthermore, the mbp1Δ strain showed 84% and 35% decreases in respiration intensity under aerobic and oxygen-limited conditions, respectively. These findings indicate that MBP1 plays an important role in responding to variations in oxygen content and is involved in the regulation of respiration and fermentation. Unexpectedly, mbp1Δ also showed pseudohyphal growth, in which cells elongated and remained connected in a multicellular arrangement on yeast extract-peptone-dextrose (YPD) plates. In addition, mbp1Δ showed an increase in cell volume, associated with a decrease in the fraction of budded cells. These results provide more detailed information about the function of MBP1 and suggest some clues to efficiently improve ethanol production by industrially engineered yeast strains. IMPORTANCE Saccharomyces cerevisiae is an especially favorable organism used for ethanol production. However, inhibitors and high osmolarity conferred by fermentation broth, and high concentrations of ethanol as fermentation runs to completion, affect cell growth and ethanol production. Therefore, yeast strains with high performance, such as rapid growth, high tolerance, and high ethanol productivity, are highly desirable. Great efforts have been made to improve their performance by evolutionary engineering, and industrial strains may be a better start than laboratory ones for industrial-scale ethanol production. The significance of our research is uncovering the function of MBP1 in ethanol fermentation in a wild-type industrial S. cerevisiae strain, which may provide clues to engineer better-performance yeast in producing ethanol. Furthermore, the results that lacking MBP1 caused pseudohyphal growth on YPD plates could shed light on the development of xylose-fermenting S. cerevisiae, as using xylose as the sole carbon source also caused pseudohyphal growth.


Assuntos
Oxigênio/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Ciclo Celular , Etanol/metabolismo , Fermentação , Deleção de Genes , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo
9.
Int J Mol Sci ; 21(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111064

RESUMO

Polysialic acid (polySia) is an unusual glycan that posttranslational modifies neural cell adhesion molecule (NCAM) proteins in mammalian cells. The up-regulated expression of polySia-NCAM is associated with tumor progression in many metastatic human cancers and in neurocognitive processes. Two members of the ST8Sia family of α2,8-polysialyltransferases (polySTs), ST8Sia II (STX) and ST8Sia IV (PST) both catalyze synthesis of polySia when activated cytidine monophosphate(CMP)-Sialic acid (CMP-Sia) is translocate into the lumen of the Golgi apparatus. Two key polybasic domains in the polySTs, the polybasic region (PBR) and the polysialyltransferase domain (PSTD) areessential forpolysialylation of the NCAM proteins. However, the precise molecular details to describe the interactions required for polysialylation remain unknown. In this study, we hypothesize that PSTD interacts with both CMP-Sia and polySia to catalyze polysialylation of the NCAM proteins. To test this hypothesis, we synthesized a 35-amino acid-PSTD peptide derived from the ST8Sia IV gene sequence and used it to study its interaction with CMP-Sia, and polySia. Our results showed for the PSTD-CMP-Sia interaction,the largest chemical-shift perturbations (CSP) were in amino acid residues V251 to A254 in the short H1 helix, located near the N-terminus of PSTD. However, larger CSP values for the PSTD-polySia interaction were observed in amino acid residues R259 to T270 in the long H2 helix. These differences suggest that CMP-Sia preferentially binds to the domain between the short H1 helix and the longer H2 helix. In contrast, polySia was principally bound to the long H2 helix of PSTD. For the PSTD-polySia interaction, a significant decrease in peak intensity was observed in the 20 amino acid residues located between the N-and C-termini of the long H2 helix in PSTD, suggesting a slower motion in these residues when polySia bound to PSTD. Specific features of the interactions between PSTD-CMP-Sia, and PSTD-polySia were further confirmed by comparing their 800 MHz-derived HSQC spectra with that of PSTD-Sia, PSTD-TriSia (DP 3) and PSTD-polySia. Based on the interactions between PSTD-CMP-Sia, PSTD-polySia, PBR-NCAM and PSTD-PBR, these findingsprovide a greater understanding of the molecular mechanisms underlying polySia-NCAM polysialylation, and thus provides a new perspective for translational pharmacological applications and development by targeting the two polysialyltransferases.


Assuntos
Ácido N-Acetilneuramínico do Monofosfato de Citidina/metabolismo , Imageamento por Ressonância Magnética/métodos , Moléculas de Adesão de Célula Nervosa/metabolismo , Ácidos Siálicos/metabolismo , Sialiltransferases/química , Sialiltransferases/metabolismo , Complexo de Golgi/metabolismo , Humanos , Modelos Moleculares , Polimerização , Conformação Proteica , Domínios Proteicos
10.
RSC Adv ; 10(4): 2267-2276, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35494577

RESUMO

Replacement of a novel candidate ethanol fermentation-associated regulatory gene, PHO4, from a fast-growing strain MC15, as determined through comparative genomics analysis among three yeast strains with significant differences in ethanol yield, is hypothesised to shorten the fermentation time and enhance ethanol production from sugarcane molasses. This study sought to test this hypothesis through a novel strategy involving the transfer of the PHO4 gene from a low ethanol-producing, yet fast-growing strain MC15 to a high ethanol-producing industrial strain MF01 through homologous recombination. The results indicated that PHO4 in the industrially engineered strain MF01-PHO4 displayed genomic stability with a mean maximum ethanol yield that rose to 114.71 g L-1, accounting for a 5.30% increase in ethanol yield and 12.5% decrease in fermentation time in comparison with that in the original strain MF01, which was the current highest ethanol-producing strain in SCM fermentation in the reported literature. These results serve to advance our current understanding of the association between improving ethanol yield and replacement of PHO4, while providing a feasible strategy for industrially engineered yeast strains to improve ethanol production efficiently.

11.
Curr Top Med Chem ; 19(25): 2271-2282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31648641

RESUMO

Polysialic acid (polySia) is a novel glycan that posttranslationally modifies neural cell adhesion molecules (NCAMs) in mammalian cells. Up-regulation of polySia-NCAM expression or NCAM polysialylation is associated with tumor cell migration and progression in many metastatic cancers and neurocognition. It has been known that two highly homologous mammalian polysialyltransferases (polySTs), ST8Sia II (STX) and ST8Sia IV (PST), can catalyze polysialylation of NCAM, and two polybasic domains, polybasic region (PBR) and polysialyltransferase domain (PSTD) in polySTs play key roles in affecting polyST activity or NCAM polysialylation. However, the molecular mechanisms of NCAM polysialylation and cell migration are still not entirely clear. In this minireview, the recent research results about the intermolecular interactions between the PBR and NCAM, the PSTD and cytidine monophosphate-sialic acid (CMP-Sia), the PSTD and polySia, and as well as the intramolecular interaction between the PBR and the PSTD within the polyST, are summarized. Based on these cooperative interactions, we have built a novel model of NCAM polysialylation and cell migration mechanisms, which may be helpful to design and develop new polysialyltransferase inhibitors.


Assuntos
Movimento Celular , Moléculas de Adesão de Célula Nervosa/metabolismo , Ácidos Siálicos/metabolismo , Animais , Humanos , Moléculas de Adesão de Célula Nervosa/química , Ácidos Siálicos/química
12.
Med Chem ; 15(5): 510-520, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30556504

RESUMO

BACKGROUND: Inhibition of α-amylase activity is an important strategy in the treatment of diabetes mellitus. An important treatment for diabetes mellitus is to reduce the digestion of carbohydrates and blood glucose concentrations. Inhibiting the activity of carbohydrate-degrading enzymes such as α-amylase and glucosidase significantly decreases the blood glucose level. Most inhibitors of α-amylase have serious adverse effects, and the α-amylase inactivation mechanisms for the design of safer inhibitors are yet to be revealed. OBJECTIVE: In this study, we focused on the inhibitory effect of Zn2+ on the structure and dynamic characteristics of α-amylase from Anoxybacillus sp. GXS-BL (AGXA), which shares the same catalytic residues and similar structures as human pancreatic and salivary α-amylase (HPA and HSA, respectively). METHODS: Circular dichroism (CD) spectra of the protein (AGXA) in the absence and presence of Zn2+ were recorded on a Chirascan instrument. The content of different secondary structures of AGXA in the absence and presence of Zn2+ was analyzed using the online SELCON3 program. An AGXA amino acid sequence similarity search was performed on the BLAST online server to find the most similar protein sequence to use as a template for homology modeling. The pocket volume measurer (POVME) program 3.0 was applied to calculate the active site pocket shape and volume, and molecular dynamics simulations were performed with the Amber14 software package. RESULTS: According to circular dichroism experiments, upon Zn2+ binding, the protein secondary structure changed obviously, with the α-helix content decreasing and ß-sheet, ß-turn and randomcoil content increasing. The structural model of AGXA showed that His217 was near the active site pocket and that Phe178 was at the outer rim of the pocket. Based on the molecular dynamics trajectories, in the free AGXA model, the dihedral angle of C-CA-CB-CG displayed both acute and planar orientations, which corresponded to the open and closed states of the active site pocket, respectively. In the AGXA-Zn model, the dihedral angle of C-CA-CB-CG only showed the planar orientation. As Zn2+ was introduced, the metal center formed a coordination interaction with H217, a cation-π interaction with W244, a coordination interaction with E242 and a cation-π interaction with F178, which prevented F178 from easily rotating to the open state and inhibited the activity of the enzyme. CONCLUSION: This research may have uncovered a subtle mechanism for inhibiting the activity of α-amylase with transition metal ions, and this finding will help to design more potent and specific inhibitors of α-amylases.


Assuntos
Inibidores Enzimáticos/farmacologia , Zinco/farmacologia , alfa-Amilases/antagonistas & inibidores , Anoxybacillus/enzimologia , Domínio Catalítico , Dicroísmo Circular , Inibidores Enzimáticos/metabolismo , Simulação de Dinâmica Molecular , Fenilalanina/química , Ligação Proteica/efeitos dos fármacos , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Conformação Proteica em Folha beta/efeitos dos fármacos , Zinco/metabolismo , alfa-Amilases/química , alfa-Amilases/isolamento & purificação , alfa-Amilases/metabolismo
13.
Sheng Wu Gong Cheng Xue Bao ; 34(5): 653-663, 2018 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-29893073

RESUMO

Spt proteins are defined as a large family of transcription regulators of the yeast Saccharomyces cerevisiae. They are crucial components of the SAGA complex that regulates transcription through interaction with the TATA box in the upstream region of the target genes. About 10% of total gene transcriptions are related to Spt proteins and these genes are highly related to environmental stress response. Such vast regulation network and complex mechanisms have become a hotspot. Spt proteins are also important to suppress transposon-induced mutations, being a switch on regulation of transposon behaviors and adaptive evolution of Saccharomyces cerevisiae. Besides that, some Spt proteins are directly involved in regulating unsaturated lipid acids synthesis, which could remold the cell membrane to resist environmental stresses. Here, we review Spt proteins, the advances in Spt proteins study, and their potential applications in improving yeast's stress resistance through transcription regulation, transposon activity regulation and cell membrane alternation.


Assuntos
Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/fisiologia , Fatores de Transcrição/fisiologia , Estresse Fisiológico , Transcrição Gênica
14.
Mol Genet Genomics ; 293(1): 265-276, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29159508

RESUMO

Mechanisms for high L-lactic acid production remain unclear in many bacteria. Lactobacillus rhamnosus SCT-10-10-60 was previously obtained from L. rhamnosus ATCC 11443 via mutagenesis and showed improved L-lactic acid production. In this study, the genomes of strains SCT-10-10-60 and ATCC 11443 were sequenced. Both genomes are a circular chromosome, 2.99 Mb in length with a GC content of approximately 46.8%. Eight split genes were identified in strain SCT-10-10-60, including two LytR family transcriptional regulators, two Rex redox-sensing transcriptional repressors, and four ABC transporters. In total, 60 significantly up-regulated genes (log2fold-change ≥ 2) and 39 significantly down-regulated genes (log2fold-change ≤ - 2) were identified by a transcriptome comparison between strains SCT-10-10-60 and ATCC 11443. KEGG pathway enrichment analysis revealed that "pyruvate metabolism" was significantly different (P < 0.05) between the two strains. The split genes and the differentially expressed genes involved in the "pyruvate metabolism" pathway are probably responsible for the increased L-lactic acid production by SCT-10-10-60. The genome and transcriptome sequencing information and comparison of SCT-10-10-60 with ATCC 11443 provide insights into the anabolism of L-lactic acid and a reference for improving L-lactic acid production using genetic engineering.


Assuntos
Genômica , Ácido Láctico/biossíntese , Lacticaseibacillus rhamnosus/genética , Transcriptoma/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Lacticaseibacillus rhamnosus/metabolismo , Engenharia Metabólica , Mutação , Ácido Pirúvico/metabolismo
15.
J Biosci Bioeng ; 123(6): 665-672, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28254341

RESUMO

Endo-polygalacturonases play an important role on depectinization in fruit juices industry. A putative endo-polygalacturonase gene PoxaEnPG28A was cloned from Penicillium oxalicum CZ1028. PoxaEnPG28A consisted of a putative signal peptide and a catalytic domain belonging to glycoside hydrolase family 28, and it shared 72% identity with that of a functionally characterized endo-polygalacturonase from Trichoderma harzianum. Gene PoxaEnPG28A was successfully expressed in Pichia pastoris with a high yield of 1828.7 U/mL. The purified recombinant enzyme PoxaEnPG28A hydrolyzed polygalacturonic acid in endo-manner releasing oligo-galacturonates. PoxaEnPG28A showed maximal activity at pH 5.5 and 55°C, and was stable between pH 3.0 to 10.0 and below 45°C. The kinetic constants Km and Vmax of PoxaEnPG28A were calculated as 1.57 g/L and 14,641.29 U/mg, respectively. PoxaEnPG28A significantly improved the yields of fruit juices from banana, plantain, papaya, pitaya and mango. The high production level of the recombinant enzyme PoxaEnPG28A by P. pastoris and remarkable catalytic activity of PoxaEnPG28A toward five kinds of fruit juices made the enzyme a potential application in agriculture and food industries.


Assuntos
Biotecnologia , Sucos de Frutas e Vegetais , Penicillium/enzimologia , Poligalacturonase/isolamento & purificação , Poligalacturonase/metabolismo , Clima Tropical , Clonagem Molecular , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Pectinas/metabolismo , Penicillium/genética , Pichia/genética , Poligalacturonase/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...