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Ya. O. Loginov G. G. Khudaigulov S. P. Chetverikov A. I. Melent’ev O. N. Loginov 《Applied Biochemistry and Microbiology》2011,47(3):311-314
Highly viscous polysaccharide (250–350 kDa) of an alginate nature with a predominance of α-L-guluronic acid (M/G = 0.22) was
obtained from Azotobacter vinelandi. The yield of polysaccharide was 20.5 ± 0.5 g/l when cultured in a medium containing molasses at a viscosity of the cultural
liquid of over 30000 cSt. The biopolymer is stable at pH 4.0–9.0 in a wide temperature range and well soluble in highly mineralized
water; it retains a high viscosity level and can be used in the petroleum industry for enhanced oil recovery. 相似文献
906.
I. A. Parfenov T. A. Revina P. P. Pashkovsky N. L. Radyukina T. A. Valueva 《Applied Biochemistry and Microbiology》2011,47(4):361-365
Product of polymerase chain reaction designated as PKPIJ-B was isolated after amplification from genomic DNA of potato (Solarium tuberosum L., Zhukov Jubilee cultivar) using the designed primers. Nucleotide sequence of PKPIJ-B was determined and amino acid sequence of protein was restored. Analysis of this sequence has allowed us to suggest that
isolated gene fragment encodes chymotrypsin and trypsin inhibitor protein (PKCI-23 potato Kunitz-type chymotrypsin inhibitor)
of potato tubers. 相似文献
907.
V. Selvakumar P. R. Anbudurai T. Balakumar 《In vitro cellular & developmental biology. Plant》2001,37(2):280-284
Summary A protocol for rapid in vitro propagation using nodal explants obtained from 2-yr-old, field-grown medicinal plants of Plumbago zeylanica L. belonging to the family Plumbaginaceae is described. High frequency bud break and fast development of shoots were induced
on Murashige and Skoog's basal medium supplemented with 27.2 μM adenine sulfate +2.46 μM indole-3-butyric acid (IBA). Induction of rooting was achieved by transferring the shoots to the same basal medium containing
4.92 μM IBA. Using our protocol from one twig of P. zeylanica (eight responsive nodes per explant shoot) within a period of 5 mo., eight plantlets could be raised. After a hardening period
of 4 wk, there was a 90% transplantation success in the field compared to the 60–65% survival of plantlets recorded in the
experiments of previous workers. The plantlets derived through in vitro propagation mimic the growth and morphological characteristics of the donor plants. 相似文献
908.
MOTIVATION: STS-content data for genomic mapping contain numerous errors and anomalies resulting in cross-links among distant regions of the genome. Identification of contigs within the data is an important and difficult problem. RESULTS: This paper introduces a graph algorithm which creates a simplified view of STS-content data. The shape of the resulting structure graph provides a quality check - coherent data produce a straight line, while anomalous data produce branches and loops. In the latter case, it is sometimes possible to disentangle the various paths into subsets of the data covering contiguous regions of the genome, i.e. contigs. These straight subgraphs can then be analyzed in standard ways to construct a physical map. A theoretical basis for the method is presented along with examples of its application to current STS data from human genome centers. AVAILABILITY: Freely available on request. 相似文献
909.
The synthesis of some monocyclic beta-lactams (monobactams) by the Staudinger reaction using D-glucosamine propanedithioacetal as chiral auxiliary is reported. The influence of several radicals at C3, C4, and C1' (sugar moiety) as well as other structural aspects are considered in relation to the antielastase activity. 相似文献
910.