Pleiotropic effect of anionic phospholipids absence on mitochondrial morphology and cell wall integrity in strictly aerobic Kluyveromyces lactis yeasts

Abstract

Cardiolipin and phosphatidylglycerol are anionic phospholipids localized to the inner mitochondrial membrane. In this study, it is demonstrated by fluorescence and transmission electron microscopy that atp2.1pgs1Δ mutant mitochondria lacking anionic phospholipids contain fragmented and swollen mitochondria with a completely disorganized inner membrane. In the second part of this study, it was shown that the temperature sensitivity of the atp2.1pgs1Δ mutant was not suppressed by the osmotic stabilizer glucitol but by glucosamine, a precursor of chitin synthesis. The atp2.1pgs1Δ mutant was hypersensitive to Calcofluor White and caffeine, resistant to Zymolyase, but its sensitivity to caspofungin was the same as the strains with the standard PGS1 gene. The distribution of chitin in the mutant cell wall was impaired. The glucan level in the cell wall of the atp2.1pgs1Δ mutant was reduced by 4-8 %, but the level of chitin was almost double that in the wild-type strain. The cell wall of the atp2.1pgs1Δ mutant was about 20 % thinner than the wild type, but its morphology was not significantly altered.

Oolong tea extract as a substitute for uranyl acetate in staining of ultrathin sections based on examples of animal tissues for transmission electron microscopy

“…Uranyl acetate (UA) was first introduced by Watson () as an electron stain for transmission electron microscopy (TEM) observations. The method involves staining the ultrathin sections with UA followed by lead salts (Pb) and has since been conventionally applied in TEM of a wide variety of samples (Reynolds, ; Sato et al ., ; Miller et al ., ; Nakakoshi et al ., ; Carpentier et al ., ; He et al ., ), due to the unrivalled image quality (Bai et al ., ; Akita et al ., ; Bardelcikova et al ., ; Fernandez‐Avila et al ., ; Herdean et al ., ; Ota et al ., ; Sobala et al ., ). However, because of the instability, high toxicity and radioactivity of UA, it has become increasingly difficult to obtain it due to strict regulations on internationally controlled nuclear materials even for scientific research purposes (Miller et al ., ).…”

“…Uranyl acetate (UA) was first introduced by Watson (1958) as an electron stain for transmission electron microscopy (TEM) observations. The method involves staining the ultrathin sections with UA followed by lead salts (Pb) and has since been conventionally applied in TEM of a wide variety of samples (Reynolds, 1963;Sato et al, 2008;Miller et al, 2010;Nakakoshi et al, 2011;Carpentier et al, 2012;He et al, 2015), due to the unrivalled image quality (Bai et al, 2015;Akita et al, 2017;Bardelcikova et al, 2016;Fernandez-Avila et al, 2016;Herdean et al, 2016;Ota et al, 2016;Sobala et al, 2016).…”