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To achieve bio-scouring or biological degumming of the flax roving, a kind of eco-friendly techniques, an alkalophilic strain was screened from the rotten wrack around Zhoushan archipelago sea area. It was characterized as Cellulomonas sp and named Cellulomonas sp DA8 by measuring the strain morphology, physiology, biochemistry, and the 16s rDNA sequences. Determination of enzyme activity showed that the activities of petinase and xylanase were obtained, and enzyme activities are stable under 50°C and at pH values in the range of 6.5 to 9.0. It was utilized to scour the flax roving under alkaline conditions, and the result showed that the strain had a good characteristic of scouring, and less strength loss of flax fiber was 14.19%. Scanning electron microscopy (SEM) showed that the gum in the flax fiber was mostly degraded, and the most smooth fiber surface was displayed, compared with fiber untreated and scoured by caustic soda.

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.

Dissociation constants and stoichiometry of binding for interaction of Cellulomonas sp. purine nucleoside phosphorylase with its substrates: inosine/guanosine, orthophosphate, guanine/hypoxanthine and D-ribose-1-phosphate were studied by kinetic and spectrofluorimetric methods.