@article{doi:10.1128/spectrum.04091-23,

title = {Development and utilization of new O_{2}-independent bioreporters},

author = {Eva Agranier and Pauline Crétin and Aurélie Joublin-Delavat and Léa Veillard and Katia Touahri and François Delavat},

url = {https://journals.asm.org/doi/abs/10.1128/spectrum.04091-23

hal-04505221v1 },

doi = {10.1128/spectrum.04091-23},

year  = {2024},

date = {2024-03-05},

urldate = {2024-03-05},

journal = {Microbiology Spectrum},

volume = {0},

number = {0},

pages = {e04091-23},

abstract = {Fluorescent proteins are used for decades, and have allowed major discoveries in biology in a wide variety of fields, and are used in environmental as well as clinical contexts. Green fluorescent protein (GFP) and all its derivatives share a common feature: they rely on the presence of dioxygen (O2) for protein maturation and fluorescence. This dependency precludes their use in anoxic environments. Here, we constructed a series of genetic circuits allowing production of KOFP-7, an O2-independant flavin-binding fluorescent protein. We demonstrated that Escherichia coli cells producing KOFP-7 are fluorescent, both at the population and single-cell levels. Importantly, we showed that, unlike cells producing GFP, cells producing KOFP-7 are fluorescent in anoxia. Finally, we demonstrated that Vibrio diazotrophicus NS1, a facultative anaerobe, is fluorescent in the absence of O2 when KOFP-7 is produced. Altogether, the development of new genetic circuits allowing O2-independent fluorescence will open new perspective to study anaerobic processes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37853951,

title = {Normal B cells express ZAP70 in chronic lymphocytic leukemia: A link between autoimmunity and lymphoproliferation?},

author = {Dana Ghergus and Mickaël Martin and Anne-Marie Knapp and Fabien Delmotte and Aurélie Joublin-Delavat and Sophie Jung and Jean-Nicolas Schickel and Isabelle Mendel and Arnaud Dupuis and Bernard Drénou and Hervé Ghesquières and Gilles Salles and Lucile Baseggio and Raoul Herbrecht and Anne-Sophie Korganow and Laurent Vallat and Pauline Soulas-Sprauel and Eric Meffre and Thierry Martin},

url = {https://hal.science/hal-04343628v1},

doi = {10.1002/ajh.27137},

issn = {1096-8652},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {Am J Hematol},

volume = {99},

number = {1},

pages = {48--56},

abstract = {ZAP70 has a prognostic value in chronic lymphocytic leukemia (CLL), through altered B-cell receptor signaling, which is important in CLL pathogenesis. A good correlation between ZAP70 expression in CLL cells and the occurrence of autoimmune phenomena has been reported. Yet, the great majority of CLL-associated autoimmune cytopenia is due to polyclonal immunoglobulin (Ig) G synthesized by nonmalignant B cells, and this phenomenon is poorly understood. Here, we show, using flow cytometry, that a substantial percentage of CD5- nonmalignant B cells from CLL patients expresses ZAP70 compared with CD5- B cells from healthy subjects. This ZAP70 expression in normal B cells from CLL patients was also evidenced by the detection of ZAP70 mRNA at single-cell level with polyclonal Ig heavy- and light-chain gene transcripts. ZAP70+ normal B cells belong to various B-cell subsets and their presence in the naïve B-cell subset suggests that ZAP70 expression may occur during early B-cell development in CLL patients and potentially before malignant transformation. The presence of ZAP70+ normal B cells is associated with autoimmune cytopenia in CLL patients in our cohort of patients, and recombinant antibodies produced from these ZAP70+ nonmalignant B cells were frequently autoreactive including anti-platelet reactivity. These results provide a better understanding of the implication of ZAP70 in CLL leukemogenesis and the mechanisms of autoimmune complications of CLL.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{joublindelavat_genetic_2022,

title = {Genetic and physiological insights into the diazotrophic activity of a non-cyanobacterial marine diazotroph},

author = {Aurélie Joublin-Delavat and Katia Touahri and Pauline Crétin and Amandine Morot and Sophie Rodrigues and Bruno Jesus and Florian Trigodet and François Delavat},

url = {https://onlinelibrary.wiley.com/doi/10.1111/1462-2920.16261

hal-03993957v1 },

doi = {10.1111/1462-2920.16261},

issn = {1462-2912, 1462-2920},

year  = {2022},

date = {2022-12-01},

urldate = {2022-12-01},

journal = {Environmental Microbiology},

volume = {24},

number = {12},

pages = {6510--6523},

abstract = {Nitrogen (N2) fixation, or diazotrophy, supports a large part of primary production in oceans. Culture-independent approaches highlighted the presence in abundance of marine non-cyanobacterial diazotrophs (NCD), but their ecophysiology remains elusive, mostly because of the low number of isolated NCD and because of the lack of available genetic tools for these isolates. Here, a dual genetic and functional approach allowed unveiling the ecophysiology of a marine NCD affiliated to the species Vibrio diazotrophicus. Physiological characterization of the first marine NCD mutant obtained so far was performed using a soft-gellan assay, demonstrating that a ΔnifH mutant is not able to grow in nitrogen-free media. Furthermore, we demonstrated that V. diazotrophicus produces a thick biofilm under diazotrophic conditions, suggesting biofilm production as an adaptive response of this NCD to cope with the inhibition of nitrogen fixation by molecular oxygen. Finally, the genomic signature of V. diazotrophicus is essentially absent from metagenomic data of Tara Ocean expeditions, despite having been isolated from various marine environments. We think that the genetically tractable V. diazotrophicus strain used in this study may serve as an ideal model to study the ecophysiology of these overlooked procaryotic group.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}