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Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) is an excellent tool for bacterial identification. It allows high throughput, sensitive and specific applications in clinical diagnostics and environmental research. Currently, there is no optimal standardized protocol for sample preparation and culture conditions to profile bacteria. The performance of MALDI‐TOF MS is affected by several variables, such as sample preparation, culture media and culture conditions, incubation time/growth stage, incubation temperature, high salt content, blood in the culture media, and others. This review thus aims to clarify why a uniformed protocol is not plausible, to assess the effects these factors have on MALDI‐TOF MS identification score, and discuss possible optimizations for its methodology, in relation to specific bacterial representatives and strain requirements. [ABSTRACT FROM AUTHOR]

Two main parameters that structure the marine ecosystem by affecting species distribution, abundance, community structure, timing of major life cycle events, and trophic state of the ecosystem are temperature and nutrient availability. Faced with climate change, eukaryotic plankton cope at multiple levels through physiological accommodation, adaptive evolution, shift in time and/or space of habitat, and/or community responses. Thirty‐two years of our phytoplankton research indicate that Chaetoceros curvisetus/pseudocurvisetus adjust to climate change more successfully than the majority of the accompanying phytoplankton taxa in the mesotrophic part of the NW Adriatic Sea, the Mediterranean. While the abundance of the entire accompanying phytoplankton community has decreased significantly since 2003 (the period of the northern Adriatic warming and oligotrophication) compared to the previous period (1986–2003), the abundance of C. curvisetus/pseudocurvisetus remained unchanged, while its contribution to the community increased significantly. Accommodation strategies include a change in the timing of high abundance and blooms in the surface layer and successful blooming in the deeper layers during warm months. Apart from the observed in situ accommodation, physiological acclimation to warming may involve changes in photosynthesis, respiration, growth, and cell biochemistry. Here, we conducted laboratory experiments with C. pseudocurvisetus to investigate how warming affects its biochemical response through the fatty acid remodeling of phospholipid classes. Long‐term field observations and short‐term laboratory experiments suggest that marine diatoms C. curvisetus/pseudocurvisetus are potential global winners with the ability to acclimate/adapt to climate change. [ABSTRACT FROM AUTHOR]

MALDI‐TOF MS was tested for the identification of Photobacterium damselae subsp. piscicida on isolates grown on two media, cultured at three incubation times and applied on the target plate by the direct sample spotting (DS), by the on‐target extraction (OTE) and by the full extraction (FE) method, in triplicates. The identification of samples grown on blood agar (BA) outperformed identification on tryptic soya agar (TSA) by 0.64% for DS and OTE. The OTE gave the highest scores in both culture media, all incubation times and replicates. Reliable 24‐hr species identification was 61.54%, 84.61% and 53.85% for samples grown on TSA and identified by DS, OTE and FE, respectively. For isolates grown on BA, they were 76.92%, 96.15% and 30.77%, respectively. When identified by OTE, the 48‐hr identification was 93.58%, but for 72 hr declined to 71.79%. The reliable identification with the highest score from the first measurement was 100% only for OTE from BA (24 hr), whereas OTE from TSA gave 84.61% (24 hr), 76.92% (48 hr) and 84.61% (72 hr). The reliable MALDI‐TOF MS identification of Ph. damselae subsp. piscicida is incubation time, media, target plate preparation and replicate‐dependent. [ABSTRACT FROM AUTHOR]

The novel N-1-sulfonylcytosine-cyclam conjugates 1 and 2 conjugates are ionized by electrospray ionization mass spectrometry (ESI MS) in positive and negative modes (ES+ and ES-) as singly protonated/deprotonated species or as singly or doubly charged metal complexes. Their structure and fragmentation behavior is examined by collision induced experiments. It was observed that the structure of the conjugate dictated the mode of the ionization: 1 was analyzed in ES- mode while 2 in positive mode. Complexation with metal ions did not have the influence on the ionization mode. Zn2+ and Cu2+ complexes with ligand 1 followed the similar fragmentation pattern in negative ionization mode. The transformation from 2°-amine in 1 to 3°-amine of cyclam ring in 2 leads to the different fragmentation patterns due to the modification of the protonation priority which changed the fragmentation channels within the conjugate itself. Cu2+ ions formed complexes practically immediately, and the priority had the cyclam portion of the ligand 2. The structure of the formed Zn2+ complexes with ligand 2 depended on the number of 3° amines within the cyclam portion of the conjugate and the ratio of the metal:ligand used. The cleavage of the cyclam ring of metal complexes is driven by the formation of the fragment that suited the coordinating demand of the metal ions and the collision energy applied. Finally, it was shown that the structure of the cyclam conjugate dictates the fragmentation reactions and not the metal ions. [ABSTRACT FROM AUTHOR]

The aim of this report is to present the electrospray ionization mass spectrometry results of the non-covalent interaction of two biologically active ligands, N-1-(p-toluenesulfonyl)cytosine, 1-TsC, 1 and N-1-methanesulfonylcytosine, 1-MsC, 2 and their Cu(II) complexes Cu(1-TsC-N3)2Cl2, 3 and Cu(1-MsC-N3)2Cl2 and 4 with biologically important cations: Na+, K+, Ca2+, Mg2+ and Zn2+. The formation of various complex metal ions was observed. The alkali metals Na+ and K+ formed clusters because of electrostatic interactions. Ca2+ and Mg2+ salts produced the tris ligand and mixed ligand complexes. The interaction of Zn2+ with 1–4 produced monometal and dimetal Zn2+ complexes as a result of the affinity of Zn2+ ions toward both O and N atoms. [ABSTRACT FROM AUTHOR]