Isolation, characterisation and genome assembly of Barnettozyma botsteinii sp. nov. and novel strains of Kurtzmaniella quercitrusa isolated from the intestinal tract of the termite Macrotermes bellicosus

Abstract Bioconversion of hemicelluloses into simpler sugars leads to production of a significant amount of pentose sugars, such as D-xylose. However, efficient utilization of pentoses by conventional yeast production strains remains challenging. Wild yeast strains can provide new industrially relevant characteristics and efficiently utilize pentose sugars. To explore this strategy, we isolated gut-residing yeasts from the termite Macrotermes bellicosus collected in Comoé National Park, Côte d´Ivoire. The yeasts were classified through their ITS/LSU sequence, their genomes were sequenced and annotated. We identified a novel yeast species, which we name Barnettozyma botsteinii sp. nov. 1118T (MycoBank: 833563, CBS 16679T and IBT 710) and two new strains of Kurtzmaniella quercitrusa: var. comoensis (CBS 16678, IBT 709) and var. filamentosus (CBS 16680, IBT 711). The two K. quercitrusa strains grow 15% faster on synthetic glucose medium than Saccharomyces cerevisiae CEN.PKT in acidic conditions (pH = 3.2) and both strains grow on D-xylose as the sole carbon source at a rate of 0.35 h−1. At neutral pH, the yeast form of K. quercitrusa var. filamentosus, but not var. comoensis, switched to filamentous growth in a carbon source dependent manner. Their genomes are 11.0-13.2 Mb in size and contain between 4888 and 5475 predicted genes. Together with closely related species, we did not find any relationship between gene content and ability to grow on xylose. Besides its metabolism, K. quercitrusa var. filamentosus also has a large potential as a production organism, because of its capacity to grow at low pH and to undergo a dimorphic shift.

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Tyrosine phosphorylation-dependent localization of TmaR that controls activity of a major bacterial sugar regulator by polar sequestration

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2016017118 ◽

2020 ◽

Vol 118 (2) ◽

pp. e2016017118

Author(s):

Tamar Szoke ◽

Nitsan Albocher ◽

Sutharsan Govindarajan ◽

Anat Nussbaum-Shochat ◽

Orna Amster-Choder

Keyword(s):

Escherichia Coli ◽

Sugar Uptake ◽

Dependent Manner ◽

Tyrosine Residue ◽

Sugar Consumption ◽

E Coli ◽

Acidic Conditions ◽

Enzyme I ◽

Uptake And Metabolism ◽

Protein Enzyme

The poles of Escherichia coli cells are emerging as hubs for major sensory systems, but the polar determinants that allocate their components to the pole are largely unknown. Here, we describe the discovery of a previously unannotated protein, TmaR, which localizes to the E. coli cell pole when phosphorylated on a tyrosine residue. TmaR is shown here to control the subcellular localization and activity of the general PTS protein Enzyme I (EI) by binding and polar sequestration of EI, thus regulating sugar uptake and metabolism. Depletion or overexpression of TmaR results in EI release from the pole or enhanced recruitment to the pole, which leads to increasing or decreasing the rate of sugar consumption, respectively. Notably, phosphorylation of TmaR is required to release EI and enable its activity. Like TmaR, the ability of EI to be recruited to the pole depends on phosphorylation of one of its tyrosines. In addition to hyperactivity in sugar consumption, the absence of TmaR also leads to detrimental effects on the ability of cells to survive in mild acidic conditions. Our results suggest that this survival defect, which is sugar- and EI-dependent, reflects the difficulty of cells lacking TmaR to enter stationary phase. Our study identifies TmaR as the first, to our knowledge, E. coli protein reported to localize in a tyrosine-dependent manner and to control the activity of other proteins by their polar sequestration and release.

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Evolutionary trade-offs between unicellularity and multicellularity in budding yeast

10.1101/347609 ◽

2018 ◽

Cited By ~ 2

Author(s):

Jennie J. Kuzdzal-Fick ◽

Lin Chen ◽

Gábor Balázsi

Keyword(s):

Mitotic Exit ◽

Fundamental Question ◽

Bet Hedging ◽

Evolutionary Transitions ◽

Wild Yeast ◽

Yeast Strains ◽

Trade Offs ◽

Mitotic Exit Network ◽

Multicellular Organisms ◽

Benefits And Costs

ABSTRACTMulticellular organisms appeared on Earth through several independent major evolutionary transitions. Are such transitions reversible? Addressing this fundamental question entails understanding the benefits and costs of multicellularity versus unicellularity. For example, some wild yeast strains form multicellular clumps, which might be beneficial in stressful conditions, but this has been untested. Here we show that unicellular yeast evolves from clump-forming ancestors by propagating samples from suspension after larger clumps have settled. Unicellular yeast strains differed from their clumping ancestors mainly by mutations in the AMN1 (Antagonist of Mitotic exit Network) gene. Ancestral yeast clumps were more resistant to freeze/thaw, hydrogen peroxide, and ethanol stressors than their unicellular counterparts, while unicellularity was advantageous without stress. These findings inform mathematical models, jointly suggesting a trade-off between the benefits and downsides of multicellularity, causing bet-hedging by regulated phenotype switching as a survival strategy in unexpected stress.

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Engineered Pentafunctional Minicellulosome for Simultaneous Saccharification and Ethanol Fermentation in Saccharomyces cerevisiae

Applied and Environmental Microbiology ◽

10.1128/aem.02070-14 ◽

2014 ◽

Vol 80 (21) ◽

pp. 6677-6684 ◽

Cited By ~ 37

Author(s):

Youyun Liang ◽

Tong Si ◽

Ee Lui Ang ◽

Huimin Zhao

Keyword(s):

Saccharomyces Cerevisiae ◽

Carbon Source ◽

Phosphoric Acid ◽

Sole Carbon Source ◽

Consolidated Bioprocessing ◽

Content Type ◽

Yeast Strains ◽

Recombinant Yeast Strain ◽

Polysaccharide Monooxygenases ◽

Simultaneous Saccharification

ABSTRACTSeveral yeast strains have been engineered to express different cellulases to achieve simultaneous saccharification and fermentation of lignocellulosic materials. However, successes in these endeavors were modest, as demonstrated by the relatively low ethanol titers and the limited ability of the engineered yeast strains to grow using cellulosic materials as the sole carbon source. Recently, substantial enhancements to the breakdown of cellulosic substrates have been observed when lytic polysaccharide monooxygenases (LPMOs) were added to traditional cellulase cocktails. LPMOs are reported to cleave cellulose oxidatively in the presence of enzymatic electron donors such as cellobiose dehydrogenases. In this study, we coexpressed LPMOs and cellobiose dehydrogenases with cellobiohydrolases, endoglucanases, and β-glucosidases inSaccharomyces cerevisiae. These enzymes were secreted and docked onto surface-displayed miniscaffoldins through cohesin-dockerin interaction to generate pentafunctional minicellulosomes. The enzymes on the miniscaffoldins acted synergistically to boost the degradation of phosphoric acid swollen cellulose and increased the ethanol titers from our previously achieved levels of 1.8 to 2.7 g/liter. In addition, the newly developed recombinant yeast strain was also able to grow using phosphoric acid swollen cellulose as the sole carbon source. The results demonstrate the promise of the pentafunctional minicellulosomes for consolidated bioprocessing by yeast.

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A phylogenetic community approach for studying termite communities in a West African savannah

Biology Letters ◽

10.1098/rsbl.2015.0625 ◽

2015 ◽

Vol 11 (10) ◽

pp. 20150625 ◽

Cited By ~ 9

Author(s):

Barbara Hausberger ◽

Judith Korb

Keyword(s):

Environmental Filtering ◽

Single Species ◽

Insect Species ◽

Conservation Strategies ◽

Closely Related Species ◽

Community Processes ◽

Community Approach ◽

Macrotermes Bellicosus ◽

Single Insect ◽

West African Savannah

Termites play fundamental roles in tropical ecosystems, and mound-building species in particular are crucial in enhancing species diversity, from plants to mammals. However, it is still unclear which factors govern the occurrence and assembly of termite communities. A phylogenetic community approach and null models of species assembly were used to examine structuring processes associated with termite community assembly in a pristine savannah. Overall, we did not find evidence for a strong influence of interspecific competition or environmental filtering in structuring these communities. However, the presence of a single species, the mound-building termite Macrotermes bellicosus , left a strong signal on structuring and led to clustered communities of more closely related species. Hence, this species changes the assembly rules for a whole community. Our results show the fundamental importance of a single insect species for community processes, suggesting that more attention to insect species is warranted when developing conservation strategies.

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Relocation of Alona manueli Sinev & Zawisza 2013 and a new closely related species from the Ecuadorian Andes to the new genus Alpinalona (Cladocera, Chydoridae, Aloninae)

Zootaxa ◽

10.11646/zootaxa.4350.3.8 ◽

2017 ◽

Vol 4350 (3) ◽

pp. 563 ◽

Cited By ~ 1

Author(s):

MIGUEL ALONSO ◽

ARTEM Y. SINEV

Keyword(s):

North America ◽

South America ◽

High Altitude ◽

Related Species ◽

National Park ◽

New Genus ◽

Ventral Surface ◽

Closely Related Species ◽

Head Pores ◽

Lateral Head

Alpinalona gen. nov. is described for two species found in high altitude localities of continental North America and South America: Alona manueli (Sinev & Zawisza, 2013) from the Neovolcanic Mexican Axis and Alpinalona cajasi gen. et sp. nov from El Cajas National Park (Ecuador). The new genus is separated from Hexalona and allies by the absence of limb VI and filter plate V; from Anthalona, Coronatella and the elegans-group by having seven setae on exopodite III, and by the presence of a well-developed seta 1 on the IDL of limb III; from Alona s. str. (quadrangularis-group) and Ovalona, by two main head pores, lateral head pores located close to main pores, and by a bilobed exopodite V; from Ovalona by the presence of seta (i) and inner setae 2–3 on limb I, and setae 4–5 of exopodite III being of same size; and from Alona s. lato by weakly developed marginal denticles of postabdomen, clusters of thin setulae on ventral surface of limb I, and by plumose setae 5–6 of exopodite IV. Alpinalona cajasi sp. nov. can be easily distinguished from A. manueli by the following characteristics: prominent posterodorsal angle of carapace; broader headshield; longer PP distance; and postanal marginal denticles organized into groups.

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p38 Mitogen-Activated Protein Kinase/Hog1p Regulates Translation of the AU-Rich-Element-Bearing MFA2 Transcript

Molecular and Cellular Biology ◽

10.1128/mcb.25.22.9753-9763.2005 ◽

2005 ◽

Vol 25 (22) ◽

pp. 9753-9763 ◽

Cited By ~ 18

Author(s):

Shobha Vasudevan ◽

Nicole Garneau ◽

Danny Tu Khounh ◽

Stuart W. Peltz

Keyword(s):

Protein Kinase ◽

Carbon Source ◽

P38 Mapk ◽

Growth Conditions ◽

Mitogen Activated Protein Kinase ◽

Stability Factor ◽

Translation Efficiency ◽

Dependent Manner ◽

Translation Repression ◽

Mitogen Activated Protein

ABSTRACT AU-rich-element (ARE)-mediated mRNA regulation occurs in Saccharomyces cerevisiae in response to external and internal stimuli through the p38 mitogen-activated protein kinase (MAPK)/Hog1p pathway. We demonstrate that the ARE-bearing MFA2 3′ untranslated region (UTR) controls translation efficiency in a p38 MAPK/Hog1p-dependent manner in response to carbon source growth conditions. The carbon source-regulated effect on MFA2 3′-UTR-controlled translation involves the role of conserved ARE binding proteins, the ELAV/TIA-1-like Pub1p, which can interact with the cap/eIF4G complex, and the translation/mRNA stability factor poly(A) binding protein (Pab1p). Pub1p binds the MFA2 3′-UTR in a p38 MAPK/Hog1p-regulated manner in response to carbon source growth conditions. Significantly, the p38 MAPK/Hog1p is also required to modulate Pab1p in response to carbon source. We find that Pab1p can bind the MFA2 3′-UTR in a regulated manner to control MFA2 3′-UTR reporter translation. Binding of full-length Pab1p to the MFA2 3′-UTR correlates with translation repression. Importantly, Pab1p binds the MFA2 3′-UTR only in a PUB1 strain, and correlating with this requirement, Pub1p controls translation repression of MFA2 in a carbon source/Hog1p-regulated manner. These results suggest that the p38 MAPK/Hog1p pathway regulates 3′-UTR-mediated translation by modulating recruitment of Pab1p and Pub1p, which can interact with the translation machinery.

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Aeromonas salmonicida Binds Differentially to Mucins Isolated from Skin and Intestinal Regions of Atlantic Salmon in anN-Acetylneuraminic Acid-Dependent Manner

Infection and Immunity ◽

10.1128/iai.01931-14 ◽

2014 ◽

Vol 82 (12) ◽

pp. 5235-5245 ◽

Cited By ~ 25

Author(s):

János T. Padra ◽

Henrik Sundh ◽

Chunsheng Jin ◽

Niclas G. Karlsson ◽

Kristina Sundell ◽

...

Keyword(s):

Atlantic Salmon ◽

Intestinal Tract ◽

Aeromonas Salmonicida ◽

High Morbidity ◽

Dependent Manner ◽

Content Type ◽

Distal Intestine ◽

Acetylneuraminic Acid ◽

Host Pathogen Interaction ◽

Glycan Chain

ABSTRACTAeromonas salmonicidasubsp.salmonicidainfection, also known as furunculosis disease, is associated with high morbidity and mortality in salmonid aquaculture. The first line of defense the pathogen encounters is the mucus layer, which is predominantly comprised of secreted mucins. Here we isolated and characterized mucins from the skin and intestinal tract of healthy Atlantic salmon and studied howA. salmonicidabound to them. The mucins from the skin, pyloric ceca, and proximal and distal intestine mainly consisted of mucins soluble in chaotropic agents. The mucin density and mucin glycan chain length from the skin were lower than were seen with mucin from the intestinal tract.A. salmonicidabound to the mucins isolated from the intestinal tract to a greater extent than to the skin mucins. The mucins from the intestinal regions had higher levels of sialylation than the skin mucins. Desialylating intestinal mucins decreasedA. salmonicidabinding, whereas desialylation of skin mucins resulted in complete loss of binding. In line with this,A. salmonicidaalso bound better to mammalian mucins with high levels of sialylation, andN-acetylneuraminic acid appeared to be the sialic acid whose presence was imperative for binding. Thus, sialylated structures are important forA. salmonicidabinding, suggesting a pivotal role for sialylation in mucosal defense. The marked differences in sialylation as well asA. salmonicidabinding between the skin and intestinal tract suggest interorgan differences in the host-pathogen interaction and in the mucin defense againstA. salmonicida.

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