Abstract
Summary Mature pollen grains of all 15 species examined release nuclease within the first minutes of contact with a liquid medium. These species include plants with both binucleate and trinucleate pollen and with biotic and abiotic modes of pollination. The enzyme of Pinus nigra pollen exhibits similar characteristics as the earlier described enzyme of tobacco pollen classified as plant nuclease I (E.C. 3.1.30.x). It is shown to be a sugar-unspecific endonuclease with maximal activity at acidic pH and preference for single-stranded molecules. The enzyme produces oligonucleotides and 5'-mononucleotides. Nuclease of the other pollen species also has more or less pronounced preference for denatured as opposed to native DNA. A pH in the range of 5.0-5.9 and 6.8-7.0 is optimal for the enzyme of dicotyledons and cereal species, respectively. Different pollen species release different amounts of nuclease with different specific activities. The enzyme also exhibits species-related variation in electrophoretic mobility and in the number of molecular forms. Molecular sieving of pine pollen diffusate produced one nuclease peak with an apparent molecular mass of 29.5 x 10 3 .
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
