scholarly journals Alternative Biochemistries for Alien Life: Basic Concepts and Requirements for the Design of a Robust Biocontainment System in Genetic Isolation

Genes ◽  
2018 ◽  
Vol 10 (1) ◽  
pp. 17 ◽  
Author(s):  
Christian Diwo ◽  
Nediljko Budisa

The universal genetic code, which is the foundation of cellular organization for almost all organisms, has fostered the exchange of genetic information from very different paths of evolution. The result of this communication network of potentially beneficial traits can be observed as modern biodiversity. Today, the genetic modification techniques of synthetic biology allow for the design of specialized organisms and their employment as tools, creating an artificial biodiversity based on the same universal genetic code. As there is no natural barrier towards the proliferation of genetic information which confers an advantage for a certain species, the naturally evolved genetic pool could be irreversibly altered if modified genetic information is exchanged. We argue that an alien genetic code which is incompatible with nature is likely to assure the inhibition of all mechanisms of genetic information transfer in an open environment. The two conceivable routes to synthetic life are either de novo cellular design or the successive alienation of a complex biological organism through laboratory evolution. Here, we present the strategies that have been utilized to fundamentally alter the genetic code in its decoding rules or its molecular representation and anticipate future avenues in the pursuit of robust biocontainment.

2020 ◽  
Vol 2 (4) ◽  
pp. 89-92
Author(s):  
Muhammad Amir ◽  
Sabeera Afzal ◽  
Alia Ishaq

Polymerases were revealed first in 1970s. Most important to the modest perception the enzyme responsible for nuclear DNA replication that was pol , for DNA repair pol and for mitochondrial DNA replication pol  DNA construction and renovation done by DNA polymerases, so directing both the constancy and discrepancy of genetic information. Replication of genome initiate with DNA template-dependent fusion of small primers of RNA. This preliminary phase in replication of DNA demarcated as de novo primer synthesis which is catalyzed by specified polymerases known as primases. Sixteen diverse DNA-synthesizing enzymes about human perspective are devoted to replication, reparation, mutilation lenience, and inconsistency of nuclear DNA. But in dissimilarity, merely one DNA polymerase has been called in mitochondria. It has been suggest that PrimPol is extremely acting the roles by re-priming DNA replication in mitochondria to permit an effective and appropriate way replication to be accomplished. Investigations from a numeral of test site have significantly amplified our appreciative of the role, recruitment and regulation of the enzyme during DNA replication. Though, we are simply just start to increase in value the versatile roles that play PrimPol in eukaryote.


2020 ◽  
Vol 133 (3) ◽  
pp. 758-764
Author(s):  
Eung Koo Yeon ◽  
Young Dae Cho ◽  
Dong Hyun Yoo ◽  
Su Hwan Lee ◽  
Hyun-Seung Kang ◽  
...  

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.


BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Tengcheng Que ◽  
Huifeng Wang ◽  
Weifei Yang ◽  
Jianbao Wu ◽  
Chenyang Hou ◽  
...  

Abstract Background Trachypithecus leucocephalus, the white-headed langur, is a critically endangered primate that is endemic to the karst mountains in the southern Guangxi province of China. Studying the genomic and transcriptomic mechanisms underlying its local adaptation could help explain its persistence within a highly specialized ecological niche. Results In this study, we used PacBio sequencing and optical assembly and Hi-C analysis to create a high-quality de novo assembly of the T. leucocephalus genome. Annotation and functional enrichment revealed many genes involved in metabolism, transport, and homeostasis, and almost all of the positively selected genes were related to mineral ion binding. The transcriptomes of 12 tissues from three T. leucocephalus individuals showed that the great majority of genes involved in mineral absorption and calcium signaling were expressed, and their gene families were significantly expanded. For example, FTH1 primarily functions in iron storage and had 20 expanded copies. Conclusions These results increase our understanding of the evolution of alkali tolerance and other traits necessary for the persistence of T. leucocephalus within an ecologically unique limestone karst environment.


2018 ◽  
Author(s):  
Daniel P Cooke ◽  
David C Wedge ◽  
Gerton Lunter

Haplotype-based variant callers, which consider physical linkage between variant sites, are currently among the best tools for germline variation discovery and genotyping from short-read sequencing data. However, almost all such tools were designed specifically for detecting common germline variation in diploid populations, and give sub-optimal results in other scenarios. Here we present Octopus, a versatile haplotype-based variant caller that uses a polymorphic Bayesian genotyping model capable of modeling sequencing data from a range of experimental designs within a unified haplotype-aware framework. We show that Octopus accurately calls de novo mutations in parent-offspring trios and germline variants in individuals, including SNVs, indels, and small complex replacements such as microinversions. In addition, using a carefully designed synthetic-tumour data set derived from clean sequencing data from a sample with known germline haplotypes, and observed mutations in large cohort of tumour samples, we show that Octopus accurately characterizes germline and somatic variation in tumours, both with and without a paired normal sample. Sequencing reads and prior information are combined to phase called genotypes of arbitrary ploidy, including those with somatic mutations. Octopus also outputs realigned evidence BAMs to aid validation and interpretation.


Author(s):  
Paweł Mackiewicz ◽  
Przemysław Biecek ◽  
Dorota Mackiewicz ◽  
Joanna Kiraga ◽  
Krystian Baczkowski ◽  
...  

1998 ◽  
Vol 274 (2) ◽  
pp. E321-E327 ◽  
Author(s):  
Frederique Diraison ◽  
Michel Beylot

To measure 1) the contribution of hepatic de novo lipogenesis (DNL) and plasma free fatty acid (FFA) reesterification to plasma triglyceride (TG) secretion, and 2) the role of oxidation and hepatic and extrahepatic reesterification in FFA utilization, five normal subjects drank deuterated water and were infused (postabsorptive state) with [1-13C]palmitate and [1,2,3-2H5]glycerol. Total lipid oxidation (Lox) was measured by indirect calorimetry. FFA oxidation (2.76 ± 0.65 μmol ⋅ kg−1 ⋅ min−1) accounted for 45% of FFA turnover rate (Rt) (1.04 μmol ⋅ kg−1 ⋅ min−1) and 91% of Lox; FFA reesterification was 3.27 ± 0.54 μmol ⋅ kg−1 ⋅ min−1. Fractional and absolute TG Rt were 0.21 ± 0.02 h−1 and 0.11 ± 0.05 μmol ⋅ kg−1 ⋅ min−1. DNL accounted for 3.9 ± 0.9% of TG secretion, and hepatic FFA reesterification accounted for 49.4 ± 5.7%; this last process represented a utilization of FFA of 0.16 ± 0.02 μmol ⋅ kg−1 ⋅ min−1. We conclude that, in the postabsorptive state, 1) DNL and FFA reesterification account for only 50–55% of TG secretion, the remaining presumably being provided by stored lipids or lipoproteins taken up by liver, 2) most reesterification occurs in extrahepatic tissues, and 3) oxidation and reesterification each contribute about one-half to FFA utilization; FFA oxidation accounts for almost all Lox.


Life ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 346
Author(s):  
Kevin G Devine ◽  
Sohan Jheeta

Modern terran life uses several essential biopolymers like nucleic acids, proteins and polysaccharides. The nucleic acids, DNA and RNA are arguably life’s most important, acting as the stores and translators of genetic information contained in their base sequences, which ultimately manifest themselves in the amino acid sequences of proteins. But just what is it about their structures; an aromatic heterocyclic base appended to a (five-atom ring) sugar-phosphate backbone that enables them to carry out these functions with such high fidelity? In the past three decades, leading chemists have created in their laboratories synthetic analogues of nucleic acids which differ from their natural counterparts in three key areas as follows: (a) replacement of the phosphate moiety with an uncharged analogue, (b) replacement of the pentose sugars ribose and deoxyribose with alternative acyclic, pentose and hexose derivatives and, finally, (c) replacement of the two heterocyclic base pairs adenine/thymine and guanine/cytosine with non-standard analogues that obey the Watson–Crick pairing rules. This manuscript will examine in detail the physical and chemical properties of these synthetic nucleic acid analogues, in particular on their abilities to serve as conveyors of genetic information. If life exists elsewhere in the universe, will it also use DNA and RNA?


Author(s):  
M. D. MADULARA ◽  
P. A. B. FRANCISCO ◽  
S. NAWANG ◽  
D. C. AROGANCIA ◽  
C. J. CELLUCCI ◽  
...  

We investigate the pairwise mutual information and transfer entropy of ten-channel, free-running electroencephalographs measured from thirteen subjects under two behavioral conditions: eyes open resting and eyes closed resting. Mutual information measures nonlinear correlations; transfer entropy determines the directionality of information transfer. For all channel pairs, mutual information is generally lower with eyes open compared to eyes closed indicating that EEG signals at different scalp sites become more dissimilar as the visual system is engaged. On the other hand, transfer entropy increases on average by almost two-fold when the eyes are opened. The largest one-way transfer entropies are to and from the Oz site consistent with the involvement of the occipital lobe in vision. The largest net transfer entropies are from F3 and F4 to almost all the other scalp sites.


Sign in / Sign up

Export Citation Format

Share Document