UHMK1 (KIS) is a nuclear serine/threonine kinase that possesses a U2AF homology motif and phosphorylates and regulates the activity of the splicing factors SF1 and SF3b155.Mutations in these components of the spliceosome machinery have been recently implicated in leukemogenesis. The fact that UHMK1 regulates these factors suggests that UHMK1 might be involved in RNA processing and perhaps leukemogenesis. Here we analyzed UHMK1 expression in normal hematopoietic and leukemic cells as well as its function in leukemia cell line.In the normal hematopoietic compartment, markedly higher levels of transcripts were Lentivirus mediated UHMK1 knockdown did not affect proliferation, cell cycle progression, apoptosis or migration of U937 leukemia cells, although UHMK1 silencing strikingly increased clonogenicity of these cells. Thus, our results suggest that UHMK1 plays a role in hematopoietic cell differentiation and suppression of autonomous clonal growth of leukemia cells.

This study explores the production and characterization of an extracellular β-fructofuranosidase (FFase-I) by Aspergillus versicolor newly isolated from Atlantic Forest-Brazil. The β-fructofuranosidase production by fungus, after the optimization process using central composite design and response surface methodology, showed that 3% (w/v) apple pomace, an initial pH 7.5, and 12 days of cultivation provided the best conditions. The β-fructofuranosidase (FFase-I) was purified from the crude extract by 75% (NH 4 ) 2 SO 4 precipitation followed by DEAE-Sephadex, and the molecular mass of the FFase-I was estimated to be 75 kDa by SDS-PAGE. Furthermore, the enzyme exhibited unusual tolerance to Cu 2+ , sodium dodecyl sulfate (SDS), Tween 80, ethanol and acetone. The purified enzyme had an optimum pH of 6.0 and was stable over an acidic pH range of 3.0-6.0. The optimum temperature of the FFase-I was 55°C but was stable at 60°C for 7 h. Thus, the β-fructofuranosidase A. versicolor which has thermal stability and activity under acidic conditions would have potential application in sugar cane molasses hydrolysis for subsequent ethanol production.

UHMK1 (KIS) is a nuclear serine/threonine kinase that possesses a U2AF homology motif and phosphorylates and regulates the activity of the splicing factors SF1 and SF3b155. Mutations in these components of the spliceosome machinery have been recently implicated in leukemogenesis. The fact that UHMK1 regulates these factors suggests that UHMK1 might be involved in RNA processing and perhaps leukemogenesis. Here we analyzed UHMK1 expression in normal hematopoietic and leukemic cells as well as its function in leukemia cell line. In the normal hematopoietic compartment, markedly higher levels of transcripts were observed in differentiated lymphocytes (CD4, CD8 and CD19) compared to the progenitor enriched subpopulation (CD34) or leukemia cell lines. UHMK1 expression was upregulated in megakaryocytic-, monocytic- and granulocytic-induced differentiation of established leukemia cell lines and in erythrocytic-induced differentiation of CD34 cells. No aberrant expression was observed in patient samples of myelodysplastic syndrome (MDS), acute myeloid (AML) or lymphoblastic (ALL) leukemia. Nonetheless, in MDS patients, increased levels of UHMK1 expression positively impacted event free and overall survival. Lentivirus mediated UHMK1 knockdown did not affect proliferation, cell cycle progression, apoptosis or migration of U937 leukemia cells, although UHMK1 silencing strikingly increased clonogenicity of these cells. Thus, our results suggest that UHMK1 plays a role in hematopoietic cell differentiation and suppression of autonomous clonal growth of leukemia cells.

Penicillium crustosum FP 11 produces two extracellular xylanase, which are designated xylanase I and II, and are induced by corn stover. In this work, xylanase II was purified 40-fold with a recovery yield of 9.2% using DEAE-Sephadex and Sephadex G-75 gel filtration, and the biochemical characteristics of the enzyme were compared with other xylanases produced by the genus Penicillium. Xylanase II exhibited a single band on SDS–PAGE, and had an apparent molecular mass of 28 kDa. The optimal temperature and pH of xylanase II activity were 50ºC and 5.5, respectively. Xylanase II had activities of 61, 53 and 55% in the presence of Mg2+, DTT and β-mercaptoethanol, respectively; however, the enzyme was strongly inhibited by 5 mM Cu2+, EDTA, and SDS. Hydrolysis of beechwood xylan released mainly xylose and short-chain xylo-oligosaccharides as final products. Thus, an assessment of the enzymatic properties of xylanase II showed that its biochemical characteristics are best suited for the saccharification of lignocellulosic biomass into fermentable sugars.

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