Building bioinformatics capacity in West Africa.

African scientists need more bioinformatics training in order to make innovative contributions to global biotechnology. To address the bioinformatics skills gap in West Africa, various training initiatives have been established in the sub-region. We present the activities of the West African Biotechnology Workshops (http://www.wabw.org/) in the past three years, and report on a symposium on bioinformatics and applied genomics in West Africa. To establish and sustain regional and national networks, stronger and increased government commitment by way of financial and infrastructural support for bioinformatics capacity building in West Africa is required.

Purification and biochemical characterization of pullulanase type I from Thermus caldophilus GK-24.

A thermostable pullulanase (pullulan 6-glucanohydrolase, EC 3.2.1.41) has been purified to homogeneity from Thermus caldophilus GK-24 by chromatographic methods, including gel-filtration and ion-exchange chromatography. The specific activity of the enzyme was increased 431-fold with a recovery of 13.2%. The purified enzyme was a monomer, M(r) = 65 kDa as estimated by SDS-PAGE and gel filtration. The pI was 6.1. The enzyme was most active at pH 5.5. The activity was maximal at 75 degrees C and stable up to 95 degrees C for 30 min at pH 5.5. The enzyme was stable to incubation from pH 3.5 to pH 8.0 at 4 degrees C for 24 h. The activity of the enzyme was stimulated by Mn2+ and Mg2+ ions. Ni2+, Ca2+, Co2+ ions and EDTA did not inhibit the enzyme activity. The enzyme hydrolyzed the alpha-1,6 linkages of amylopectin, glycogens, alpha, beta-limited dextrin, and pullulan. The enzyme caused the complete hydrolysis of pullulan to maltotriose. The activity was inhibited by alpha-, beta-, or gamma-cyclodextrins. The N-terminal sequence [(AIa-Pro-Gln-(Asp or Tyr)- Asn-Leu-Leu-Xaa-ILe-Gly-Ala(Ser)] showed some similarity to those of bacterial pullulanases.