New microorganism isolation techniques with emphasis on laser printing

The study of biodiversity, growth, development, and metabolism of cultivated microorganisms is an integral part of modern microbiological, biotechnological, and medical research. Such studies require the development of new methods of isolation, cultivation, manipulation, and study of individual bacterial cells and their consortia. To this end, in recent years, there has been an active development of different isolation and three-dimensional cell positioning methods. In this review, the optical tweezers, surface heterogeneous functionalization, multiphoton lithography, microfluidic techniques, and laser printing are reviewed. Laser printing is considered as one of the most promising techniques and is discussed in detail

Design, characteristics and scientific tasks of the LASMA-LR laser ionization mass spectrometer onboard Luna-25 and Luna-27 space missions

The laser-ionization time-of-flight mass spectrometer LASMA-LR is part of the scientific payload of the Luna-25 and Luna-27 missions. The instrument is able to perform analysis of elemental and isotopic composition of solid samples (regolith and dust) with high accuracy and high spatial resolution. The principle of the instrument operation consists in complete atomization and ionization of the substance by a laser pulse, separation of ions during their free expansion, depending on their mass and charge, and subsequent registration of the ions time of flight from the sample to the detector. The instrument has small dimensions (130 × 206 × 254 mm), low weight (2.8 kg) and low mean operating power consumption (8 W). The limits of detection for element analysis are at least 50 ppmA (ppm atomic fraction) in one mass spectrum and 5 ppmA at analysis of an accumulation of 100 mass spectra. The scientific data which will be obtained by LASMA-LR can be essential for a wide range of studies, such as the geological characteristics of spacecraft landing sites, analysis of the lunar dust composition, search for rare earth elements, native metals and alloys, determination of the content of chemically bound water in regolith, and others. Achievement of these tasks will contribute to the study of fundamental questions ranging from the formation and evolution history of the Moon to the advancement of a number of applied problems of the Moon exploration and colonization. With the LASMA-LR instrument we have demonstrated that it is possible to provide all these analytical capabilities in a very compact, lightweight and at low power, which lends itself to operational concepts not only for robotic probes landed on the Moon, but also for proposed human spaceflight missions to the Moon and robotic missions to asteroids for the local prospection of mineral resources with a portable device, possibly as equipment carried by astronauts during their surface missions

Laser MICROSAMPLING of soil microbial community

Standard microorganism isolating technology applied for complex multiphase environmental samples such as soil or sediment needs pre-treatment steps to remove living cells from their mixed-phase microniche, by creating a liquid-phase sample. This process removes synergetic relationships, which help to maintain viability of yet-to-be-cultured and hard-to-culture bacteria. In this paper we demonstrate a high throughput Laser Micro-Sampling (LMS) technology for direct isolation of pure microbial cultures and microbial consortia from soil. This technology is based on laser printing of soil microparticles by focusing near-infrared laser pulses on specially prepared samples of a soil/gel mixture spread onto a gold-coated glass plate. Microsamples of soil are printed on glucose-peptone-yeast agar plates, to estimate the LMS process influence on functional and taxonomic microbial diversity, and on «Eco-log» sole carbon sources microplates, to investigate functional diversity by "metabolic fingerprinting". The obtained results are compared with traditionally treated soil samples. It was shown that LMS treatment leads to increasing of cultured biodiversity and modifies the functional diversity. The strain of rare genus Nonomuraea was isolated by LMS from complex natural environment without using media selective for this genus

EFFECT OF MACROPLASTIC ON SOIL INVERTEBRATES: A CASE STUDY USING MORPHOLOGICAL AND MOLECULAR APPROACHES

Soil contamination by plastic is a global problem. Most experimental studies focus on microplastics, but large fragments, such as a variety of packaging and plastic bags, make up a significant component of plastic pollution. The effects of large fragments of household plastic debris on soil invertebrate communities are largely unexplored. The use of metabarcoding can greatly simplify the assessment of the taxonomic composition of soil invertebrates as well as their symbionts and parasites. However, the method is still underdeveloped and requires verification by classical approaches. We used metabarcoding and the traditional approach based on the morphological identification of invertebrates in assessing the effect of macroplastics on soil animal communities. Fragments of transparent or black polyethylene film measuring 40 × 40 cm were fixed on the soil surface in four forest ecosystems. After 9 months, the total abundance of mesofauna in general and individual groups of invertebrates (Collembola, Mesostigmata) was significantly reduced in the soil under the film compared to the control plots. The presence of the film did not affect the abundance of macrofauna, but in some biotopes the abundance of Isopoda, Hemiptera and Chilopoda increased and the number of Coleoptera and Diptera larvae decreased under the plastic film. The applied modification of metabarcoding revealed a significantly lower diversity of invertebrates (66 families, 105 genera) compared to the morphological method of identification (95 families, 127 genera). Wolbachia and Rickettsia, typical endosymbionts of invertebrates, but not other common parasites, were noted. In contrast to the morphological method of determination, metabarcoding revealed no significant differences in the taxonomic composition of invertebrates in the soil under the film and in the control soil. However, the significant correlation between the results of morphological identification and metabarcoding confirms the ability of metabarcoding to detect even small changes in the taxonomic composition of soil invertebrate communities