Przemysław Malec | Jagiellonian University (original) (raw)

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Papers by Przemysław Malec

EPR study of thylakoid membrane dynamics in mutants of the carotenoid biosynthesis pathway of Syn... more EPR study of thylakoid membrane dynamics in mutants of the carotenoid biosynthesis pathway of Synechocystis sp. PCC6803*

The COP9 complex is a regulator essential for repression of light-mediated development in Arabido... more The COP9 complex is a regulator essential for repression of light-mediated development in Arabidopsis. Using partial amino acid sequence data generated from purified COP9 complexes, we cloned the Arabidopsis cDNA encoding the 27-kD subunit of the COP9 complex and showed that it is encoded by the previously identified

Journal of Applied Microbiology, 2021

This study sought to utilize indigenous soil micro‐organisms to suppress wilt‐causing fungal path... more This study sought to utilize indigenous soil micro‐organisms to suppress wilt‐causing fungal pathogens of the banana.

Acta Biochimica Polonica, 2012

Protochlorophyllide (Pchlide) accumulation and xantophyll composition were studied in 5-day old e... more Protochlorophyllide (Pchlide) accumulation and xantophyll composition were studied in 5-day old etiolated seedlings of three ecotypes of Arabidopsis thaliana: Columbia (Col-0), Landsberg erecta (Ler) and Wassiliewska (Ws). The total Pchlide level as measured by fluorescence spectroscopy varied significantly between ecotypes. A rapid HPLC method revealed quantitative differences in carotenoid composition. It was found that in the Ler ecotype any enhanced accumulation of Pchlide correlates with an increased level of lutein, suggesting the role of enzymes involved in lutein synthesis in cross-regulation between chlorophyll and carotenoid biosynthetic pathways. The function of the dark-accumulated carotenoid pool in seedling de-etiolation is discussed.

Acta Physiologiae Plantarum

ABSTRACT

Plant & cell physiology, Jan 16, 2014

In the thylakoid membranes of the mesophilic cyanobacterium Synechocystis PCC6803, PSI reaction c... more In the thylakoid membranes of the mesophilic cyanobacterium Synechocystis PCC6803, PSI reaction centers (RCs) are organized as monomers and trimers. PsaL, a 16 kDa hydrophobic protein, a subunit of the PSI RC, was previously identified as crucial for the formation of PSI trimers. In this work, the physiological effects accompanied by PSI oligomerization were studied using a PsaL-deficient mutant (ΔpsaL), not able to form PSI trimers, grown at various temperatures. We demonstrate that in wild-type Synechocystis, the monomer to trimer ratio depends on the growth temperature. The inactivation of the psaL gene in Synechocystis grown phototropically at 30°C induces profound morphological changes, including the accumulation of glycogen granules localized in the cytoplasm, resulting in the separation of particular thylakoid layers. The carotenoid composition in ΔpsaL shows that PSI monomerization leads to an increased accumulation of myxoxantophyll, zeaxanthin and echinenone irrespective o...

Journal of Trace Elements in Medicine and Biology, 2009

Evidence for Zn protection against Cd-induced reactive oxygen species in the free-floating hydrop... more Evidence for Zn protection against Cd-induced reactive oxygen species in the free-floating hydrophyte Ceratophyllum demersum L. is presented in this paper. Metal treatments of 10 micromol/L Cd, 10 Cd micromol/L supplemented with Zn (10, 50, 100 and 200 micromol/L) and Zn-alone treatments of the same concentrations were used. Using 5,5 dimethyl pyrroline-N-oxide as the spin-probe, electron spin resonance spectra indicated a drastic increase in hydroxyl radicals (OH()) in Cd-10 micromol/L treatments, which was closely correlating with the enhanced formation of hydrogen peroxide (H(2)O(2)) and generation of superoxide radical (O(2)(-)) triggered by the oxidation of NADPH. The supplementation of adding Zn (10-200 micromol/L) to the Cd-10 micromol/L treatments significantly decreased the production of free radicals especially by eliminating the precursors of OH() through inhibition of NADPH oxidation. Cd-enhanced ROS production which substantially increased the oxidative products of proteins measured as carbonyls was effectively inhibited by Zn supplementation.

Acta Biologica Cracoviensia Series Botanica, 2013

The Arabidopsis CDKG;2 gene encodes a putative cyclin-dependent Ser/Thr protein kinase of unknown... more The Arabidopsis CDKG;2 gene encodes a putative cyclin-dependent Ser/Thr protein kinase of unknown biological function. This gene shows structural similarity to animal and human cyclin-dependent (PITSLRE) kinases. This study used the homozygous knockout cdkg;2 mutant based on T-DNA insertional line SALK_090262 to study the effect of mutation of the CDKG;2 gene on explant response and in vitro plant regeneration. For callus induction and proliferation, hypocotyls and cotyledons of 3-day-old seedlings of cdkg;2 and A. thaliana ecotype Col-0 were cultured on solid MS medium supplemented with 2,4-D (2 mg l-1). Organogenesis was induced after callus transfer on MS + TDZ (0.5 mg l-1). The initiation time of callus and shoot induction differed between the mutant and control cultures. Shoot regeneration after callus transfer on MS + TDZ was delayed in cdkg;2 (31 days versus 7 days in Col-0). Shoots formed on callus derived from Col-0 hypocotyls but not on cotyledon-derived callus; in cdkg;2, shoots developed on both callus types. Mutant shoots did not form roots, regenerants were dwarfed, and inflorescences had small bud-like flowers with a reduced corolla and generative organs. Abnormalities observed during cdkg;2 organogenesis suggest a role of CDKG;2 as a regulator of adventitious root initiation.

Acta Biologica Cracoviensia. Series Botanica. Supplement, 2011

Acta Biologica Cracoviensia. Series Botanica. Supplement, 2009

Acta Biologica Cracoviensia. Series Botanica. Supplement, 2008