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The research was aimed to evaluate the effect of biogas liquid waste as a fermentation starter of rice husk to the nutrient content, gross energy and bulk density. The method used laboratory experiment using a completely randomized design (CRD) on factorial pattern (6 x 5) with the level of biogas waste liquid : P0-treatment (0% negative control), P0+ (Cellulomonas sp as positive control), P1 (5%), P2 (10%), P3 (15%), P4 (20%) ml/g, and the incubation time : T0 (0 day control ), T1(7 days), T2 (14 days), T3 (21 days) and T4 (28 days). The variables measured was the content of ash, crude protein, crude fiber, crude fat, gross energy and bulk density. Data were analyzed by analysis of variance (anova) CRD Factorial pattern and if there is a significant difference was followed by Duncan's Multiple Range Test. The results of research was the level of biogas liquid waste and the incubation time provides a significant influence (P

AIMS Lignocellulosic biomass deconstruction is a bottleneck for obtaining biofuels and value-added products. Our main goal was to characterize the secretome of a novel isolate, Cellulomonas sp. B6, when grown on residual biomass for the formulation of cost-efficient enzymatic cocktails. METHODS AND RESULTS We identified 205 potential CAZymes in the genome of Cellulomonas sp. B6, 91 of which were glycoside hydrolases (GH). By secretome analysis of supernatants from cultures in either extruded wheat straw (EWS), grinded sugar cane straw (SCR) or carboxymethylcellulose (CMC), we identified which proteins played a role in lignocellulose deconstruction. Growth on CMC resulted in the secretion of two exoglucanases (GH6 and GH48) and two GH10 xylanases, while growth on SCR or EWS resulted in the identification of a diversity of CAZymes. From the 32 GHs predicted to be secreted, 22 were identified in supernatants from EWS and/or SCR cultures, including endo- and exoglucanases, xylanases, a xyloglucanase, an arabinofuranosidase/β-xylosidase, a β-glucosidase and an AA10. Surprisingly, among the xylanases, seven were GH10. CONCLUSIONS Growth of Cellulomonas sp. B6 on lignocellulosic biomass induced the secretion of a diverse repertoire of CAZymes. SIGNIFICANCE AND IMPACT OF THE STUDY Cellulomonas sp. B6 could serve as a source of lignocellulose-degrading enzymes applicable to bioprocessing and biotechnological industries.

Complex formation of multisubstrate analogue inhibitor--2-amino-9-[2-(phosphonomethoxy)ethyl]-6-sulfanylpurine (PME-6-thio-Gua) with trimeric purine nucleoside phosphorylase from Cellulomonas sp. was investigated using a stopped-flow spectrofluorimetric approach. Results obtained indicate that, in contrast to binding of guanine, i.e., the transition-state conformation trapping ligand, for which binding at each active site is followed by the enzyme conformational change, association of the ground-state analogue PME-6-thio-Gua is a one-step process.

Novel 1H-pyrazolo[3,4-b]quinoxalines (flavazoles) 14, 15 and 1-aryl-3-quinoxalinyl-1,2,4-triazole 17 were synthesized from the ester 11 via various hydrazones 12, 13 and 16. In the antibacterial screening test of compounds 12–17, compound 14 showed a relatively high antibacterial activity, wherein the MIC value was 25 μg/ml against Bacillus licheniformis KTCC 21425 and Cellulomonas sp. and 50 μg/ml against Salmonella typhimurium KCTC 1925 and Flavobacterium devolans.

The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

The commercially available enzyme purine nucleoside phosphorylase (PNP) from Cellulomonas sp. was purified by ion-­exchange chromatography, partially sequenced and crystallized in two different crystal forms using the hanging-drop vapour-diffusion technique. Crystal form A grows as polyeders and/or cubes in the cubic space group P4232 with unit-cell dimension a = 162.5 A. Crystal form B appears as thick plates in the space group P212121 with unit-cell dimensions a = 63.2, b = 108.3 and c = 117.4 A. Both crystal forms contain three monomers (one trimer) in the asymmetric unit.

A cellulolytic bacterium has been isolated from soil and identified as a Cellulomonas sp. Optimization of media components and environmental factors led to a 17-fold increase in cellulase activity within 40 h. The trace elements Zn2+, Co2+ and Cu2+ caused severe inhibition, which could be reduced by the addition of EDTA. The enzymes endoglucanase, exoglucanase and xylanase were always present irrespective of the carbon source used.

A culture of Cellulomonas sp. and Bacillus subtilis was grown using sugar cane bagasse pith from unburnt sugar cane (UCP) as the source of carbohydrates. The yield and production values were proved to be higher than those obtained with burnt sugar cane (BCP).

Six major components exhibiting endo-1,4-\-d-glucanase activity were partially purified from culture filtrates of a newly isolated Cellulomonas sp. using ion-exchange chromatography. Molecular weights (44,000 to 140,000), pH optima (6.0 to 7.0), temperature optima (40 to 50°C), half-life, energy of activation, Kmand other kinetic parameter investigations indicate the existence of 6 different endoglucanases. Further support for this assumption comes from inhibition studies, whereby glucose inhibited the enzyme activities between 15 and 50% at a concentration of 0.034% (1.65 mM) and cellobiose between 0 and 50% at a concentration of 0.1% (2.92 mM). Of all the metals (Hg2+, Co2+, Cu2+, Ca2+, Mg2+, Zn2+, Fe3+) tested, only Hg2+ exhibited a 55% inhibition at 5.0 mM.