Evidence for the presence of kinetin in DNA and cell extracts

Abstract

In contrast to the current view that kinetin (N 6-furfuryladenine) is an unnatural and synthetic compound, we have detected it in commercially available DNA, in freshly extracted cellular DNA from human cells and in plant cell extracts by two independent methods. First, we discovered that N6-furforyladenine has electrochemical properties that can be applied for monitoring this modified base by a HPLC/UVIEC method. Second, we have confirmed electrochemical assignments by mass-spectrometric analysis. A pathway of kinetin formation is proposed in which the formation of furfural by oxidative damage of the deoxyribose moiety of DNA is followed by its reaction with adenine residues to form N6-furfuryladenine. Since this modification can lead to mutations, the odd DNA base has to be removed by repair enzymes.

The content of endogenous hormones and sugars in the process of early somatic embryogenesis in the tree fern Cyathea delgadii Sternb.

“…Although the occurrence of Kin has been considered to be an artefact, its presence had already been found in plant material such as coconut chunks (Barciszewski et al 1996) and water extracts (Ge et al 2005), root nodules of Australian pine (Raman and Elumalai 1996) as well as triticale anthers (Żur et al 2015). The importance of Kin in controlling different physiological processes in plants may be associated with its antioxidant and ABAantagonistic properties (Barciszewski et al 1996;Żur et al 2015). The key question of our research is how the content/ratio of phytohormones, established as a result of etiolation of the donor plantlets, promotes SE induction?…”

Kinetin Inhibits Protein Oxidation and Glycoxidation in Vitro

“…It is unlikely that kinetin could quench sugars or carbonyl compounds and limit their reactivity towards the amino groups of proteins, because kinetin does not possess amino groups susceptible to glycation (1,20). Since the formation of crosslinking glycoxidation products, such as pentosidine, is facilitated under oxidation, kinetin could inhibit its formation by decreasing the ROS formation or by scavenging the ROS formed in vitro by autoxidation of sugars (18).…”

“…Therefore, it appears that the N 6 -furfuryl substitution is important for the protective functions of kinetin. Paradoxically, this substitution is due to ROS damage and seems responsible for the antioxidant proprieties of kinetin thereby making kinetin more easily oxidized than adenine (20).…”

High Performance Liquid Chromatography/Electrochemistry/High Resolution Electrospray Ionization‐Mass Spectrometry (HPLC/EC/HR ESI‐MS) Characterization of Selected Cytokinins Oxidation Products

“…Besides the isomerization from tZ, another resource origin of cZ has been confirmed to tRNA (which also contains tZ, albeit in~40 times lower concentration) [33]. Since cB, cG and cH have the m/z and molecular formula exactly the same as a naturally occurring CK kinetin, which is also known to originate from nucleic acid by DNA oxidation [34], further investigation of these three cZ oxidation products is necessary, since two of them (cG and cH) have also a close retention time to kinetin. Furthermore, the possibility of such cyclization in EC cell has been confirmed for dopamine [35].…”