A snapshot of evolution in action: emergence of new heme transport function derived from a coenzyme B 12 biosynthetic enzyme

2016 ◽  
Vol 19 (1) ◽  
pp. 8-10
Author(s):  
Norbert K. Tavares ◽  
Jorge C. Escalante‐Semerena
Author(s):  
Anna Viktorovna Pirog ◽  
Olga Vladimirovna Lozhnichenko

The study of the growth of blood cells and hemopoietic organs of claravia catfish ( Clarias gariepius ) grown in the closed loop water systems on the basis of "RANTOP AGRO-5" LLC in the Krasnodar region. Test materials (prolarvae and larvae aged 5, 10, 15, 20 and 25 days of active feeding) were selected in the spring-summer period of 2013-2014. Prolarvae in mesenchyma of forming mesonephros which begins to develop after hatching had primordial precursor cell and blast blood cells between forming vesicles. There took place differentiation of erythropoietic cells: erythroblasts, pronormoblasts and basophilic normoblasts. Accumulation of hemoglobin in erythrocytes indicates that since the first day of hatching, the blood starts to perform transport function - transportation of oxygen. The rudiment of thymus was observed in larvae aged 10 days. This organ generated lymphocytepoietic cells. The central hemopoietic organ - spleen - was originally registered as a mesenchymal rudiment at the age of 10 days. At the age of 25 days, development of the organ stroma is not finished in clarid catfish larvae. Reticular tissues develop actively. Separate lymphoid clumps in the spleen structure have not been found. Melano-macrofagic centres are also unformed. Qualitative analysis of haemopoiesis showed that in spleen there take place development of all types of blood cells: erythropoiesis, granulopoiesis and agranulopoiesis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sami Havukainen ◽  
Jonai Pujol-Giménez ◽  
Mari Valkonen ◽  
Ann Westerholm-Parvinen ◽  
Matthias A. Hediger ◽  
...  

AbstractTrichoderma reesei is an ascomycete fungus known for its capability to secrete high amounts of extracellular cellulose- and hemicellulose-degrading enzymes. These enzymes are utilized in the production of second-generation biofuels and T. reesei is a well-established host for their production. Although this species has gained considerable interest in the scientific literature, the sugar transportome of T. reesei remains poorly characterized. Better understanding of the proteins involved in the transport of different sugars could be utilized for engineering better enzyme production strains. In this study we aimed to shed light on this matter by characterizing multiple T. reesei transporters capable of transporting various types of sugars. We used phylogenetics to select transporters for expression in Xenopus laevis oocytes to screen for transport activities. Of the 18 tested transporters, 8 were found to be functional in oocytes. 10 transporters in total were investigated in oocytes and in yeast, and for 3 of them no transport function had been described in literature. This comprehensive analysis provides a large body of new knowledge about T. reesei sugar transporters, and further establishes X. laevis oocytes as a valuable tool for studying fungal sugar transporters.


Genetics ◽  
1998 ◽  
Vol 150 (2) ◽  
pp. 553-562
Author(s):  
Margaret I Kanipes ◽  
John E Hill ◽  
Susan A Henry

Abstract The isolation of mutants of Schizosaccharomyces pombe defective in the synthesis of phosphatidylcholine via the methylation of phosphatidylethanolamine is reported. These mutants are choline auxotrophs and fall into two unlinked complementation groups, cho1 and cho2. We also report the analysis of the cho1+ gene, the first structural gene encoding a phospholipid biosynthetic enzyme from S. pombe to be cloned and characterized. The cho1+ gene disruption mutant (cho1Δ) is viable if choline is supplied and resembles the cho1 mutants isolated after mutagenesis. Sequence analysis of the cho1+ gene indicates that it encodes a protein closely related to phospholipid methyltransferases from Saccharomyces cerevisiae and rat. Phospholipid methyltransferases encoded by a rat liver cDNA and the S. cerevisiae OPI3 gene are both able to complement the choline auxotrophy of the S. pombe cho1 mutants. These results suggest that both the structure and function of the phospholipid N-methyltransferases are broadly conserved among eukaryotic organisms.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jasmin Frey ◽  
Sophie Kaßner ◽  
Dieter Spiteller ◽  
Mario Mergelsberg ◽  
Matthias Boll ◽  
...  

Abstract Background Degradation of acetone by aerobic and nitrate-reducing bacteria can proceed via carboxylation to acetoacetate and subsequent thiolytic cleavage to two acetyl residues. A different strategy was identified in the sulfate-reducing bacterium Desulfococcus biacutus that involves formylation of acetone to 2-hydroxyisobutyryl-CoA. Results Utilization of short-chain ketones (acetone, butanone, 2-pentanone and 3-pentanone) and isopropanol by the sulfate reducer Desulfosarcina cetonica was investigated by differential proteome analyses and enzyme assays. Two-dimensional protein gel electrophoresis indicated that D. cetonica during growth with acetone expresses enzymes homologous to those described for Desulfococcus biacutus: a thiamine diphosphate (TDP)-requiring enzyme, two subunits of a B12-dependent mutase, and a NAD+-dependent dehydrogenase. Total proteomics of cell-free extracts confirmed these results and identified several additional ketone-inducible proteins. Acetone is activated, most likely mediated by the TDP-dependent enzyme, to a branched-chain CoA-ester, 2-hydroxyisobutyryl-CoA. This compound is linearized to 3-hydroxybutyryl-CoA by a coenzyme B12-dependent mutase followed by oxidation to acetoacetyl-CoA by a dehydrogenase. Proteomic analysis of isopropanol- and butanone-grown cells revealed the expression of a set of enzymes identical to that expressed during growth with acetone. Enzyme assays with cell-free extract of isopropanol- and butanone-grown cells support a B12-dependent isomerization. After growth with 2-pentanone or 3-pentanone, similar protein patterns were observed in cell-free extracts as those found after growth with acetone. Conclusions According to these results, butanone and isopropanol, as well as the two pentanone isomers, are degraded by the same enzymes that are used also in acetone degradation. Our results indicate that the degradation of several short-chain ketones appears to be initiated by TDP-dependent formylation in sulfate-reducing bacteria.


Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 705
Author(s):  
Awdhesh Kumar Mishra ◽  
Kwang-Hyun Baek

Salicylic acid (SA) is an active secondary metabolite that occurs in bacteria, fungi, and plants. SA and its derivatives (collectively called salicylates) are synthesized from chorismate (derived from shikimate pathway). SA is considered an important phytohormone that regulates various aspects of plant growth, environmental stress, and defense responses against pathogens. Besides plants, a large number of bacterial species, such as Pseudomonas, Bacillus, Azospirillum, Salmonella, Achromobacter, Vibrio, Yersinia, and Mycobacteria, have been reported to synthesize salicylates through the NRPS/PKS biosynthetic gene clusters. This bacterial salicylate production is often linked to the biosynthesis of small ferric-ion-chelating molecules, salicyl-derived siderophores (known as catecholate) under iron-limited conditions. Although bacteria possess entirely different biosynthetic pathways from plants, they share one common biosynthetic enzyme, isochorismate synthase, which converts chorismate to isochorismate, a common precursor for synthesizing SA. Additionally, SA in plants and bacteria can undergo several modifications to carry out their specific functions. In this review, we will systematically focus on the plant and bacterial salicylate biosynthesis and its metabolism.


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