The efficient degradation mechanism of clostridium difficile and its fibrous cellulose.

Transmutal elements in the genome are widely used in nature in the positional variable DNA sequence, in the stability of the genome, genetic variation and biological evolution plays an important role. The insertion sequence (Insert sequence, IS) in the
bacterial genome is a widely existing transposonal element that can be divided into families (known to have 29 family insertion sequences) according to its sequence and mechanisms, of which IS3 is one of the most widely distributed families.
at present, the cognition of the mechanism of insertion sequence mainly comes from the study of medium-temperature microorganisms, but the genome shows that thermal-ehabiting microorganisms also contain a large number of insertion sequences, and their transpostorism mechanism has not been studied in depth.
thermal-phospholist microorganisms have special research and industrial application value because of their unique and high thermal lyse, and play an important role in biological refining.
, for example, the typical heat-obsessed microorganism of clostridium coccora is very promising in the bio-refining of lignocellulose industry.
based on this, the Institute of Bioenergy and Process of the Chinese Academy of Sciences, the Institute of Metabolites and other non-modal microorganisms, developed a high-efficiency genetic operation platform, including based on heat-obsessed second-class inclusions of targeted gene-knocking tools and scar-free genome editing tools based on homologous recombination, and used these tools to study the thermal ficobacteria and its small fibers on the ligory cellulose degradation mechanism.
in the development of a genome editing tool for clostridium, the researchers used adenosine kinase (Tdk) as a resieve marker and found that the anti-sieve marker was often inactivated by a very active IS3 family inserted into the sequence OF IS1447. Liu Yajun, an associate researcher in the
research team, and others studied the insertion sequence in depth, and through genomic search and evolutionary relationship analysis, found that is1447 similar insertion sequences are widely present in the bacteria of thick-walled bacteria, which have very unique characteristics in the insertion sequence of the IS3 family and represent a new subgroup in the IS3 family.
IS1447 subgroup to achieve the synthesis of functional full-length transposonase by the 1st bit transcription slip, which is a completely different transfer method from the known IS3 family of ribosome-1-bit translation horizontal transcoding, and this transcription slip requires only 7 consecutive adesinuaine nucleotides (A), which is different from the current lysy at least 8 consecutive A or T transcriptoating slip mechanism.
in addition, the genomes of multiple cellulose-degradable bacteria contain a very large number of IS1447 subgroup insertion sequences.
the above studies show that IS1447 represents a new IS3 subgroup insertion sequence rich in thick-walled bacteria, enriching awareness of the thermal transposing element and providing the basis for the development of insertion-based mutation-based tools used by heat-thirsty microorganisms.
diagram: IS1447 sequence from thermoficoccal bacteria and its transcription slip displacement point analysis.
IS1447 can express three transposons OrfA, OrfB and OrfAB, of which OrfAB is a functional full-length transpostorase.
purple represents the reverse repeat sequence, green and red represent the start and end sites of transposlase translation, and Huang Liang represents the shifting area.
the above-mentioned work was recently published in Biotechnology for Biofuels and was directed by Feng Yingang and Cui Ball, researchers at Qingdao Energy Institute, and Liu Yajun, the first author of the paper, supported by projects from the Ministry of Science and Technology, the National Natural Science Foundation of China, Shandong Province and the Chinese Academy of Sciences.
Papers: Liu Y-J, Qi K, Zhang J, Chen C, Cui Q, Feng Y. Firmicutes-enriched IS1447 a group of IS3-family article sings sings exhibiting unique? Biotechnology for Biofuels. 2018;11:300.Source:Qingdao Institute of Bioenergy and Process.