scholarly journals Comparative Genomic Analysis Determines the Functional Genes Related to Bile Salt Resistance in Lactobacillus salivarius

2021 ◽  
Vol 9 (10) ◽  
pp. 2038
Author(s):  
Qiqi Pan ◽  
Xudan Shen ◽  
Leilei Yu ◽  
Fengwei Tian ◽  
Jianxin Zhao ◽  
...  
Keyword(s):  
Salt Tolerance ◽  
Bile Salt ◽  
Molecular Mechanisms ◽  
Gene Knockout ◽  
Salt Resistance ◽  
Rapid Screening ◽  
Functional Genes ◽  
Comparative Genomic ◽  
Lactobacillus Salivarius ◽  
Encoding Gene

Lactobacillus salivarius has drawn attention because of its promising probiotic functions. Tolerance to the gastrointestinal tract condition is crucial for orally administrated probiotics to exert their functions. However, previous studies of L. salivarius have only focused on the bile salt resistance of particular strains, without uncovering the common molecular mechanisms of this species. Therefore, in this study, we expanded our research to 90 L. salivarius strains to explore their common functional genes for bile salt resistance. First, the survival rates of the 90 L. salivarius strains in 0.3% bile salt solutions were determined. Comparative genomics analysis was then performed to screen for the potential functional genes related to bile salt tolerance. Next, real-time polymerase chain reaction and gene knockout experiments were conducted to further verify the tolerance-related functional genes. The results indicated that the strain-dependent bile salt tolerance of L. salivarius was mainly associated with four peptidoglycan synthesis-related genes, seven phosphotransferase system-related genes, and one chaperone-encoding gene involved in the stress response. Among them, the GATase1-encoding gene showed the most significant association with bile salt tolerance. In addition, four genes related to DNA damage repair and substance transport were redundant in the strains with high bile salt tolerance. Besides, cluster analysis showed that bile salt hydrolases did not contribute to the bile salt tolerance of L. salivarius. In this study, we determined the global regulatory genes, including LSL_1568, LSL_1716 and LSL_1709, for bile salt tolerance in L. salivarius and provided a potential method for the rapid screening of bile salt-tolerant L. salivarius strains, based on PCR amplification of functional genes.

scholarly journals The Polyketide Synthase-Encoding Gene Crpks is Involved in Clonostachys Rosea Chlamydospore Formation

2020 ◽  
Author(s):  
Zhan-Bin Sun ◽  
Qi Wang ◽  
Yu-Wei Zhang ◽  
Man-Hong Sun ◽  
Shi-Dong Li
Keyword(s):  
Molecular Mechanisms ◽  
Polyketide Synthase ◽  
Wild Type Strain ◽  
Biological Function ◽  
Gene Knockout ◽  
Type I ◽  
Wild Type ◽  
Clonostachys Rosea ◽  
Chlamydospore Formation ◽  
Encoding Gene

Abstract Clonostachys rosea is an excellent agent for biocontrol of numerous plant fungal diseases. Polyketide synthases (PKSs) are widely distributed in plants and microorganisms and synthesize various types of polyketides. In this study, a type I PKS-encoding gene, crpks, was cloned and identified from the C. rosea 67-1 genome, and the biological function was investigated through gene knockout. The results showed that crpks deletion did not affect C. rosea morphology, ability for parasitism of sclerotia and the capacity for biocontrol of soybean Sclerotinia white mold, but had a marked influence on the chlamydospore formation ability of C. rosea. After cultivation for 48 and 72 h, chlamydospore production by ∆crpks was increased by 70.1% and 47.6%, respectively, compared to that of the wild-type strain. These data indicate that crpks is involved in C. rosea chlamydospore formation and provide useful insights into the molecular mechanisms of chlamydospore formation in C. rosea.

Molecular mechanisms of local adaptation for salt‐tolerance in a treefrog

2021 ◽  
Author(s):  
Molly A. Albecker ◽  
Adam M.M. Stuckert ◽  
Christopher N. Balakrishnan ◽  
Michael W. McCoy
Keyword(s):  
Salt Tolerance ◽  
Local Adaptation ◽  
Molecular Mechanisms

scholarly journals Impact of gamma irradiation pretreatment on biochemical and molecular responses of potato growing under salt stress

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Elhamahmy Ali Mohamed ◽  
Elsadany Osama ◽  
Eid Manal ◽  
Abdelazeem Samah ◽  
Gerish Salah ◽  
...  
Keyword(s):  
Salt Tolerance ◽  
Genetic Marker ◽  
Gamma Rays ◽  
Salt Resistance ◽  
Base Pairs ◽  
Potato Genotype ◽  
Potato Callus ◽  
Primer Sequence ◽  
Significant Increment

Abstract Background Previous literatures revealed that gamma rays have an increasing effect on salt tolerance in different plants. In vitro experiment was conducted to study the effect of gamma rays (20 Gray) on salt tolerance of four potato cultivars (Lady Rosetta, Diamante, Gold, and Santana). Results Gamma-treated Santana plantlets were more tolerant to salinity as compared to other cultivars. It showed a significant increment of fresh weight (250% over the untreated). Gamma-treated plantlets of Lady Rosetta, Diamante, and Gold showed higher activity of peroxidase (POD) and polyphenol oxidase (PPO). Isoenzymes analysis showed an absence of POD 3, 4, and 5 in Gold plantlets. The dye of most PODs and PPOs bands were denser (more active) in gamma-treated plantlets of Santana as compared to other cultivars. Both gamma-treated and untreated plantlets showed the absence of PPO1 in Lady Rosetta and Diamante, and PPO 3, 4, and 5 in Gold plantlets. Genetic marker analysis using ISSR with six different primers showed obvious unique negative and positive bands with different base pairs in mutant plantlets as compared to the control, according to primer sequence and potato genotype. The 14A primer was an efficient genetic marker between mutated and unmutated potato genotypes. Santana had a unique fingerprint in the 1430-pb site, which can be a selectable marker for the cultivar. An increment in genetic distance between Gold cultivar and others proved that the mutation was induced because of gamma rays. Conclusion We assume that irradiation of potato callus by 20-Gy gamma rays is an effective process for inducing salt resistance. However, this finding should be verified under field conditions. Graphic Abstract

scholarly journals STUDI VIABILITAS ISOLAT BAKTERI ASAM LAKTAT YANG DIISOLASI DARI ASINAN REBUNG BAMBU TABAH TERHADAP pH RENDAH DAN GARAM EMPEDU

2019 ◽  
Vol 7 (1) ◽  
pp. 1 ◽  
Author(s):  
Nurul Octavia Wasis ◽  
Nyoman Semadi Antara ◽  
Ida Bagus Wayan Gunam
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bile Salt ◽  
Bile Salts ◽  
Salt Resistance ◽  
Low Ph ◽  
Fermented Food ◽  
Bamboo Shoot ◽  
Probiotic Lactic Acid Bacteria ◽  
Mrs Broth

Tabah bamboo shoot pickle is one of the fermented food which is the source of lactic acid bacteria.  Lactic acid bacteria (LAB) is beneficial to health because it has the ability as a probiotic. Lactic acid bacteria that have probiotic criteria should have resistance to low pH and bile salts. This study aims to determine isolates of lactic acid bacteria isolated from tabah bamboo shoot pickle resistant to low pH and bile salts (NaDC). Lactic acid bacteria were tested to low pH by using MRS broth that have different pH (pH 2, pH 3, pH 4 and pH 6.2 as a control) incubated at 37ºC for 3 hours. isolates were survive in low pH then continued in bile salt resistance test with 0.3% bile salt concentration for 15 minutes, 30 minutes, 45 minutes, 60 minutes and 24 hours. The results showed that three isolates out of 88 isolates had ability to grow in low pH and in medium supplemented by NaDC 0,3%. The isolates are AR 3057, AR 3101 and AR 6152 which can be used as candidat of  probiotic. Keywords : Tabah bamboo shoot pickle, lactic acid bacteria, probiotic, low pH, bile salt

scholarly journals Bile Salt Homeostasis in Normal and Bsep Gene Knockout Rats with Single and Repeated Doses of Troglitazone

2017 ◽  
Vol 362 (3) ◽  
pp. 385-394 ◽  
Author(s):  
Yaofeng Cheng ◽  
Shenjue Chen ◽  
Chris Freeden ◽  
Weiqi Chen ◽  
Yueping Zhang ◽  
...  
Keyword(s):  
Bile Salt ◽  
Gene Knockout ◽  
Repeated Doses ◽  
Salt Homeostasis

scholarly journals Comparative Genomic Analysis and a Novel Set of Missense Mutation of the Leptospira weilii Serogroup Mini From the Urine of Asymptomatic Dogs in Thailand

2021 ◽  
Vol 12 ◽  
Author(s):  
Alongkorn Kurilung ◽  
Vincent Perreten ◽  
Nuvee Prapasarakul
Keyword(s):  
Molecular Mechanisms ◽  
Genome Structure ◽  
Ecological Niches ◽  
Comparative Genomic ◽  
Genomic Feature ◽  
Missense Mutations ◽  
Limited Information ◽  
High Genetic Diversity ◽  
Pan Genome ◽  
Pathogenesis Related

Leptospira weilii belongs to the pathogenic Leptospira group and is a causal agent of human and animal leptospirosis in many world regions. L. weilii can produce varied clinical presentations from asymptomatic through acute to chronic infections and occupy several ecological niches. Nevertheless, the genomic feature and genetic basis behind the host adaptability of L. weilii remain elusive due to limited information. Therefore, this study aimed to examine the complete circular genomes of two new L. weilii serogroup Mini strains (CUDO6 and CUD13) recovered from the urine of asymptomatic dogs in Thailand and then compared with the 17 genomes available for L. weilii. Variant calling analysis (VCA) was also undertaken to gain potential insight into the missense mutations, focusing on the known pathogenesis-related genes. Whole genome sequences revealed that the CUDO6 and CUD13 strains each contained two chromosomes and one plasmid, with average genome size and G+C content of 4.37 Mbp and 40.7%, respectively. Both strains harbored almost all the confirmed pathogenesis-related genes in Leptospira. Two novel plasmid sequences, pDO6 and pD13, were identified in the strains CUDO6 and CUD13. Both plasmids contained genes responsible for stress response that may play important roles in bacterial adaptation during persistence in the kidneys. The core-single nucleotide polymorphisms phylogeny demonstrated that both strains had a close genetic relationship. Amongst the 19 L. weilii strains analyzed, the pan-genome analysis showed an open pan-genome structure, correlated with their high genetic diversity. VCA identified missense mutations in genes involved in endoflagella, lipopolysaccharide (LPS) structure, mammalian cell entry protein, and hemolytic activities, and may be associated with host-adaptation in the strains. Missense mutations of the endoflagella genes of CUDO6 and CUD13 were associated with loss of motility. These findings extend the knowledge about the pathogenic molecular mechanisms and genomic evolution of this important zoonotic pathogen.

scholarly journals Physiological and transcriptomic analyses reveal the mechanisms underlying the salt tolerance of Zoysia japonica Steud.

2020 ◽  
Author(s):  
Jingjing Wang ◽  
Cong An ◽  
Hailin Guo ◽  
Xiangyang Yang ◽  
Jingbo Chen ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Salt Stress ◽  
Stress Response ◽  
Salt Tolerance ◽  
Molecular Mechanisms ◽  
Salt Tolerant ◽  
Zoysia Japonica ◽  
Salt Stress Response ◽  
Leaves And Roots ◽  
Time Point

Abstract Background: Areas with saline soils are sparsely populated and have fragile ecosystems, which severely restricts the sustainable development of local economies. Zoysia grasses are recognized as excellent warm-season turfgrasses worldwide, with high salt tolerance and superior growth in saline-alkali soils. However, the mechanism underlying the salt tolerance of Zoysia species remains unknown. Results: The phenotypic and physiological responses of two contrasting materials, Zoysia japonica Steud. Z004 (salt sensitive) and Z011 (salt tolerant) in response to salt stress were studied. The results show that Z011 was more salt tolerant than was Z004, with the former presenting greater K+/Na+ ratios in both its leaves and roots. To study the molecular mechanisms underlying salt tolerance further, we compared the transcriptomes of the two materials at different time points (0 h, 1 h, 24 h, and 72 h) and from different tissues (leaves and roots) under salt treatment. The 24-h time point and the roots might make significant contributions to the salt tolerance. Moreover, GO and KEGG analyses of different comparisons revealed that the key DEGs participating in the salt-stress response belonged to the hormone pathway, various TF families and the DUF family. Conclusions: Z011 may have improved salt tolerance by reducing Na+ transport from the roots to the leaves, increasing K+ absorption in the roots and reducing K+ secretion from the leaves to maintain a significantly greater K+/Na+ ratio. Twenty-four hours might be a relatively important time point for the salt-stress response of zoysiagrass. The auxin signal transduction family, ABA signal transduction family, WRKY TF family and bHLH TF family may be the most important families in Zoysia salt-stress regulation. This study provides fundamental information concerning the salt-stress response of Zoysia and improves the understanding of molecular mechanisms in salt-tolerant plants.

scholarly journals Ablation of the MiR-17-92 MicroRNA Cluster in Germ Cells Causes Subfertility in Female Mice

2018 ◽  
Vol 45 (2) ◽  
pp. 491-504 ◽  
Author(s):  
Jian Wang ◽  
Bo Xu ◽  
Geng G. Tian ◽  
Tao Sun ◽  
Ji Wu
Keyword(s):  
Germ Cells ◽  
Molecular Mechanisms ◽  
Gene Knockout ◽  
Conditional Knockout ◽  
Luciferase Reporter ◽  
Transcriptional Level ◽  
Follicular Atresia ◽  
Apoptotic Pathway ◽  
Female Mice ◽  
Important Regulator

Background/Aims: Oogenesis is a highly complex process that is intricately regulated by interactions of multiple genes and signaling molecules. However, the underlying molecular mechanisms are poorly understood. There is emerging evidence that microRNAs contribute to oogenesis. Here, we aimed to investigate the role of miR-17-92 cluster in regulating oogenesis. Methods: The miR-17-92 cluster was genetically ablated in germ cells of female mice by applying the Cre-loxp system for conditional gene knockout. Mating experiment, superovulation and histological analysis were used to assess the fertility of the model female mice. TUNEL assay was used to identify apoptotic cells in ovaries. The expression level of apoptosis- and follicular atresia- related genes was evaluated by qRT-PCR. Western blotting was performed to detect protein expression. Bioinformatics software and dual luciferase reporter assay were applied to predict and verify the target of miR-17-92 cluster. Results: Deletion of miR-17-92 cluster in germ cells of female mice caused increased oocyte degradation and follicular atresia, perturbed oogenesis, and ultimately led to subfertility. Genes involved in follicular atresia and the mitochondrial apoptotic pathway were obviously up-regulated. Furthermore, we verified that miR-19a regulated oogenesis at the post-transcriptional level by targeting Bmf in the ovaries of miR-17-92 cluster conditional knockout female mice. Conclusion: The miR-17-92 cluster is an important regulator of oogenesis. These findings will assist in better understanding the etiology of disorders in oogenesis and in developing new therapeutic targets for female infertility.

Molecular mechanisms driving the in vivo development of OXA-10-mediated resistance to ceftolozane/tazobactam and ceftazidime/avibactam during treatment of XDR Pseudomonas aeruginosa infections

2020 ◽  
Vol 76 (1) ◽  
pp. 91-100
Author(s):  
Jorge Arca-Suárez ◽  
Cristina Lasarte-Monterrubio ◽  
Bruno-Kotska Rodiño-Janeiro ◽  
Gabriel Cabot ◽  
Juan Carlos Vázquez-Ucha ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Molecular Mechanisms ◽  
Genomic Analysis ◽  
Resistance Mechanisms ◽  
Comparative Genomic ◽  
Development Of Resistance ◽  
Structural Impact ◽  
Genetic Context

Abstract Background The development of resistance to ceftolozane/tazobactam and ceftazidime/avibactam during treatment of Pseudomonas aeruginosa infections is concerning. Objectives Characterization of the mechanisms leading to the development of OXA-10-mediated resistance to ceftolozane/tazobactam and ceftazidime/avibactam during treatment of XDR P. aeruginosa infections. Methods Four paired ceftolozane/tazobactam- and ceftazidime/avibactam-susceptible/resistant isolates were evaluated. MICs were determined by broth microdilution. STs, resistance mechanisms and genetic context of β-lactamases were determined by genotypic methods, including WGS. The OXA-10 variants were cloned in PAO1 to assess their impact on resistance. Models for the OXA-10 derivatives were constructed to evaluate the structural impact of the amino acid changes. Results The same XDR ST253 P. aeruginosa clone was detected in all four cases evaluated. All initial isolates showed OprD deficiency, produced an OXA-10 enzyme and were susceptible to ceftazidime, ceftolozane/tazobactam, ceftazidime/avibactam and colistin. During treatment, the isolates developed resistance to all cephalosporins. Comparative genomic analysis revealed that the evolved resistant isolates had acquired mutations in the OXA-10 enzyme: OXA-14 (Gly157Asp), OXA-794 (Trp154Cys), OXA-795 (ΔPhe153-Trp154) and OXA-824 (Asn143Lys). PAO1 transformants producing the evolved OXA-10 derivatives showed enhanced ceftolozane/tazobactam and ceftazidime/avibactam resistance but decreased meropenem MICs in a PAO1 background. Imipenem/relebactam retained activity against all strains. Homology models revealed important changes in regions adjacent to the active site of the OXA-10 enzyme. The blaOXA-10 gene was plasmid borne and acquired due to transposition of Tn6746 in the pHUPM plasmid scaffold. Conclusions Modification of OXA-10 is a mechanism involved in the in vivo acquisition of resistance to cephalosporin/β-lactamase inhibitor combinations in P. aeruginosa.

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