Characterization of Soft-rot-resistant Amorphophallus konjac and Preliminary Analysis of the Resistance Mechanism

Abstract Background The emergence of carbapenem-resistant and colistin-resistant ECC pose a huge challenge to infection control. The purpose of this study was to clarify the mechanism of the carbapenems and colistin co-resistance in Enterobacter cloacae Complex (ECC) strains. Results This study showed that the mechanisms of carbapenem resistance in this study are: 1. Generating carbapenemase (7 of 19); 2. The production of AmpC or ESBLs combined with decreased expression of out membrane protein (12 of 19). hsp60 sequence analysis suggested 10 of 19 the strains belong to colistin hetero-resistant clusters and the mechanism of colistin resistance is increasing expression of acrA in the efflux pump AcrAB-TolC alone (18 of 19) or accompanied by a decrease of affinity between colistin and outer membrane caused by the modification of lipid A (14 of 19). Moreover, an ECC strain co-harboring plasmid-mediated mcr-4.3 and blaNDM-1 has been found. Conclusions This study suggested that there is no overlap between the resistance mechanism of co-resistant ECC strains to carbapenem and colistin. However, the emergence of strain co-harboring plasmid-mediated resistance genes indicated that ECC is a potential carrier for the horizontal spread of carbapenems and colistin resistance.

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Characterization of blackleg and soft rot from potato in northern Thailand

Journal of Phytopathology ◽

10.1111/jph.12859 ◽

2019 ◽

Vol 167 (11-12) ◽

pp. 655-666 ◽

Cited By ~ 2

Author(s):

Athidtaya Kumvinit ◽

Angsana Akarapisan

Keyword(s):

Soft Rot ◽

Northern Thailand

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Playing the Whack-A-Mole Game: ERK5 Activation Emerges Among the Resistance Mechanisms to RAF-MEK1/2-ERK1/2- Targeted Therapy

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.647311 ◽

2021 ◽

Vol 9 ◽

Author(s):

Alessandro Tubita ◽

Ignazia Tusa ◽

Elisabetta Rovida

Keyword(s):

Tyrosine Kinases ◽

Resistance Mechanism ◽

Resistance Mechanisms ◽

Mitogen Activated Protein Kinase ◽

Cancer Therapies ◽

New Era ◽

Mitogen Activated Protein ◽

The Impact ◽

The Ideal

Molecularly tailored therapies have opened a new era, chronic myeloid leukemia being the ideal example, in the treatment of cancer. However, available therapeutic options are still unsatisfactory in many types of cancer, and often fail due to the occurrence of resistance mechanisms. With regard to small-molecule compounds targeting the components of the Mitogen-Activated Protein Kinase (MAPK) cascade RAF-MEK1/2-ERK1/2, these drugs may result ineffective as a consequence of the activation of compensatory pro-survival/proliferative signals, including receptor tyrosine kinases, PI3K, as well as other components of the MAPK family such as TPL2/COT. The MAPK ERK5 has been identified as a key signaling molecule in the biology of several types of cancer. In this review, we report pieces of evidence regarding the activation of the MEK5-ERK5 pathway as a resistance mechanism to RAF-MEK1/2-ERK1/2 inhibitors. We also highlight the known and possible mechanisms underlying the cross-talks between the ERK1/2 and the ERK5 pathways, the characterization of which is of great importance to maximize, in the future, the impact of RAF-MEK1/2-ERK1/2 targeting. Finally, we emphasize the need of developing additional therapeutically relevant MEK5-ERK5 inhibitors to be used for combined treatments, thus preventing the onset of resistance to cancer therapies relying on RAF-MEK1/2-ERK1/2 inhibitors.

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HEAVY METAL-RESISTANT RHIZOBACTERIA FROM GOLD MINE IN PONGKOR INDONESIA AND COPPER MINE IN MARINDUQUE PHILIPPINES

Agric ◽

10.24246/agric.2019.v31.i1.p75-88 ◽

2019 ◽

Vol 31 (1) ◽

pp. 75-88 ◽

Cited By ~ 1

Author(s):

Erny Yuniarti ◽

Ida F Dalmacio ◽

Erlinda S Paterno

Keyword(s):

Resistance Mechanism ◽

Morphological Characterization ◽

Gold Mine ◽

Isolation Medium ◽

Mine Site ◽

Copper Mine ◽

Gram Staining ◽

16S Rna ◽

Agar Media

The purposes of the study was to isolate, to characterize, and to identify rhizobacteria from plant rhizosphere growing in gold and copper mine. The isolation of rhizobacteria used N-free semisolid agar media, TSA, and SLP plus heavy metals (HMs), namely Pb, Cd, and or Cu. Isolated rhizobacteria were subsequently characterized for resistance to higher level of Pb, Cd, Cu in SLP media. Cultural and morphological characterization of rhizobacteria were conducted for cell morphology, motility, Gram staining, and biofilm formation. The rhizobacteria identification used sequence analysis of the 16S RNA gene fragments. The results showed that the majority of rhizobacterial from Cu mine site (66.7% of 21 isolates) were resistant to Cu (72150 ppm) while the majority of rhizobacteria from gold mine site (77.8% of 18 isolates) were sensitive to 72 ppm Cu. Majority of Cu in the soil was insoluble as granules attaching to gravel so that rhizobacteria of Cu mine site have been exposed and adapted to available Cu. This fact, explaining that the rhizobacteria’s MIC value was lower than the total Cu level in the soil. Three HMs-resistant rhizobacter (PbSM 2.1, MGR 334, and CuNFbM 4.1) formed biofilms, which was as one of the resistance mechanism to HMs. This research informed that HM contaminated-soil is better source for obtaining HM resistant rhizobacteria than HM uncontaminated-soil. The use four isolation media produce rhizobacteria which was more diverse than rhizobacteria from each isolation medium. Further characterization needs to be done to obtain HM resistant-rhizobacteria which can be used as biofertilizers and phytoremediation agent.

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