In the presence of L-arabinose as sole carbon source, Fusarium oxysporum produces two alpha-L-arabinofuranosidases (ABFs) named ABF1 and ABF2, with molecular masses of 200 and 180 kDa, respectively. The two F. oxysporum proteins have been purified to homogeneity. The purified enzymes are composed of three equal subunits and are neutral proteins with pIs of 6.0 and 7.3 for ABF1 and ABF2, respectively. With p-nitrophenyl alpha-L-arabinofuranoside (pNPA) as the substrate, ABF1 and ABF2 exhibited Km values of 0.39 and 0.28 mmol.L(-1), respectively, and Vmax values of 1.6 and 4.6 micromol.min(-1).(mg of protein)(-1), respectively, and displayed optimal activity at pH 6.0 and 50-60 degrees C. ABFs released arabinose only from sugar beet arabinan and not from wheat soluble and insoluble arabinoxylans. The enzymes were not active on substrates containing ferulic acid ester linked to C-5 and C-2 linkages of pNPA showing that phenolic substituents of pNPA sterically hindered the action of ABFs.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1139/w03-077 | DOI Listing |
Plant Divers
November 2024
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
Salinity is a severe abiotic stress that affects plant growth and yield. Salinity stress activates jasmonate (JA) signaling in , but the underlying molecular mechanism remains to be elucidated. In this study, we confirmed the activation of JA signaling under saline conditions and demonstrated the importance of the CORONATINE INSENSITIVE1 (COI1)-mediated JA signaling for this process.
View Article and Find Full Text PDFPharmaceutics
November 2024
Centre for Pharmaceutical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia.
: Treatment of cutaneous wound infections is becoming a major clinical challenge due to the growing problem of antimicrobial resistance associated with existing wound treatments. Two prevalent pathogens in wound infections, () and (), continue to present a serious challenge, underscoring the critical need for new therapeutic alternatives. : Novel alginate acid-buffered gels (ABF-1, ABF-2, and ABF-3) were developed using a combination of organic acids in various concentrations and buffered at a pH of 4.
View Article and Find Full Text PDFJ Plant Physiol
February 2024
Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, Sichuan, China. Electronic address:
The phytohormone abscisic acid (ABA) regulates plant growth and development and stress resistance through the ABA receptor PYLs. To date, no interaction between CPK and PYL has been reported, even in Arabidopsis and rice. In this study, we found that MdCPK4 from Malus domestica (Md for short) interacts with two MdPYLs, MdPYL2/12, in the nucleus and the cytoplasm in vivo and phosphorylates the latter in vitro as well.
View Article and Find Full Text PDFPlant Physiol
September 2023
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
CONSTANS (CO) is a critical regulator of flowering that combines photoperiodic and circadian signals in Arabidopsis (Arabidopsis thaliana). CO is expressed in multiple tissues, including seedling roots and young leaves. However, the roles and underlying mechanisms of CO in modulating physiological processes outside of flowering remain obscure.
View Article and Find Full Text PDFFront Plant Sci
June 2023
Henry Fok School of Biology and Agriculture, Guangdong Engineering Technology Research Center for Efficient Utilization of Water and Soil Resources in North Region, Shaoguan University, Shaoguan, Guangdong, China.
Partial root-zone drying (PRD) is an effective water-saving irrigation strategy that improves stress tolerance and facilitates efficient water use in several crops. It has long been considered that abscisic acid (ABA)-dependent drought resistance may be involved during partial root-zone drying. However, the molecular mechanisms underlying PRD-mediated stress tolerance remain unclear.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!