The amino acid sequence of ancestral enzymes from extinct organisms can be deduced through in silico approach termed ancestral sequence reconstruction (ASR). ASR usually has six steps, which are the collection of nucleic acid/amino acid sequences of modern enzymes, multiple sequence alignment, phylogenetic tree construction, computational deduction of ancestral enzyme sequence, gene cloning, and characterization of enzyme properties. This method is widely used to study the adaptation and evolution mechanism of molecules to the changing environmental conditions on planetary time scale. As enzymes play key roles in biocatalysis, this method has become a powerful method for studying the relationship among the sequence, structure, and function of enzymes. Notably, most of the ancestral enzymes show better temperature stability and mutation stability, making them ideal protein scaffolds for further directed evolution. This article summarizes the computer algorithms, applications, and commonly used computer software of ASR, and discusses the potential application in directed evolution of enzymes.
Amino Acid Sequence ; Evolution, Molecular ; Phylogeny ; Proteins/genetics* ; Sequence Alignment

The nucleotide sequence and N-, C-terminal amino acid sequences of alpha,beta-subunit of glutaryl 7-ACA acylase C130 from Pseudomonas sp. 130 were determined. The alignment of the acylase C130 with the other acylases shows that it has high homology with the acylases from Pseudomonas sp. GK16 and C427, but low homology with the others. There is large difference in the N-terminal of alpha-subunit, while the N-terminal of beta-subunit has significant conservation.
Amino Acid Sequence ; Base Sequence ; DNA, Bacterial ; analysis ; Genes, Bacterial ; Molecular Sequence Data ; Penicillin Amidase ; genetics ; Pseudomonas ; enzymology ; genetics ; Sequence Homology, Amino Acid ; Sequence Homology, Nucleic Acid

Human defensin is a family of cationic antimicrobial peptides in human being. During the last two decades a series of endogenous alpha-and beta-human defensins have been discovered. They are important components of the first barrier in human's body against the invasion of various microorganisms, and they are thought to play an important role in linking the innate and adaptive defense system of human being. The recent advances in the research of human defensins were reviewed, including their discovery, molecular and genetic properties, expression regulation, and mechanisms of antimicrobial activity. The possibility to produce human defensins via genetic engineering was also discussed. And the application outlook of human defensins in medicine and curing patients infected with antibiotics-resistant microbials was presented.
Amino Acid Sequence ; Defensins ; chemistry ; genetics ; metabolism ; physiology ; Genetic Engineering ; Humans ; Molecular Sequence Data ; Sequence Homology, Amino Acid

The purpose of this study was to clone and characterize the ZFP36L1 (zinc finger protein 36-like 1) gene, clarify its expression characteristics, and elucidate its expression patterns in different tissues of goats. Samples of 15 tissues from Jianzhou big-eared goats, including heart, liver, spleen, lung and kidney were collected. Goat ZFP36L1 gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR), then the gene and protein sequence were analyzed by online tools. Quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression level of ZFP36L1 in intramuscular preadipocytes in different tissues and adipocytes of goat at different differentiation stages. The results showed that the length of ZFR36L1 gene was 1 224 bp, and the coding sequence (CDS) region was 1 017 bp, encoding 338 amino acids, which was a non-secretory unstable protein mainly located in nucleus and cytoplasm. Tissue expression profile showed that ZFP36L1 gene was expressed in all selected tissues. In visceral tissues, the small intestine showed the highest expression level (P < 0.01). In muscle tissue, the highest expression level was presented in longissimus dorsi muscle (P < 0.01), whereas the expression level in subcutaneous adipose tissue was significantly higher than that in other tissues (P < 0.01). The results of induced differentiation showed that the expression of this gene was up-regulated during adipogenic differentiation of intramuscular precursor adipocytes (P < 0.01). These data may help to clarify the biological function of the ZFP36L1 gene in goat.
Animals ; Goats/genetics* ; Amino Acid Sequence ; Liver ; Cloning, Molecular

OBJECTIVETo study the EV71 Chinese strain SHZH98 and analyze its genetic evolution using 3c gene as index.

METHODSThe 3C gene cDNA of EV71 Chinese strain SHZH98 was amplified by PCR, the PCR product was sequenced.

RESULTSThe EV71 Chinese mainland strain SHZH98 3C segment was 549 bps in length. Comparison of nucleotide sequences from other enteroviruses which have been published, revealed a higher homology to strain MS, 78.7% at nucleotide level and 93.45% at deduced amino acid level. The homology to strain BrCr was 76.7% at nucleotide level and 89.1% at deduced amino acid level. Taiwan strains POLY,NCKU,TW2086,TW2272 shared a lower homology with Chinese mainland strain SHZH98, 74.0%, 73.8%, 71.9%, 69.8% at nucleotide level and 90.7%, 90.2%, 84.2%, 82.5% at deduced amino acid level. The genetic progress analysis revealed that EV71 Chinese mainland strain SHZH98 3C segment shares more homology with European and American strains than Taiwan strains.

CONCLUSIONThe non-structural protein of EV71 Chinese strains may have different evolutionary process from Taiwan strains.

Amino Acid Sequence ; Base Sequence ; Enterovirus ; genetics ; isolation & purification ; Genes, Viral ; Humans ; Molecular Sequence Data ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Homology, Amino Acid ; Sequence Homology, Nucleic Acid

Mutation (substitution, deletion, insertion, etc.) in nucleotide acid causes the maximal sequence lengths of exact match (MALE) between paralogous members from a duplicate event to become shorter during evolution. In this work, MALE changes between members of 26 gene families from four representative species (Arabidopsis thaliana, Oryza sativa, Mus musculus and Homo sapiens) were investigated. Comparative study of paralogous' MALE and amino acid substitution rate (d(A)<0.5) indicated that a close relationship existed between them. The results suggested that MALE could be a sound evolutionary scale for the divergent time for paralogous genes during their early evolution. A reference table between MALE and divergent time for the four species was set up, which would be useful widely, for large-scale genome alignment and comparison. As an example, detection of large-scale duplication events of rice genome based on the table was illustrated.
Amino Acid Sequence ; Amino Acid Substitution ; Animals ; Arabidopsis ; genetics ; Chromosome Mapping ; methods ; Conserved Sequence ; genetics ; Evolution, Molecular ; Humans ; Mice ; Molecular Sequence Data ; Oryza ; genetics ; Proteome ; genetics ; metabolism ; Sequence Alignment ; methods ; Sequence Analysis, Protein ; methods ; Sequence Homology, Amino Acid ; Species Specificity

A full-length cDNA of GGPPS gene from Tripterygium wilfordii suspension cells was obtained by use of RACE strategy (GeneBank: KM978333), and then analyzed by bioinformatics approaches. TwGGPPS cDNA has 1857 nucleotides and an open reading frame (ORF) encoding a protein of 514 amino acid residues. The deduced protein has isoelectric point (pI) of 7.85, a calculated molecular weight about 57.13 kD, 5 conserved domains and 2 functional domains. PSORT Prediction showed it was located at plasma membrane. Phylogenetic analysis demonstrated that TwGGPPS1 was similar to GGPPS from other species of plants. For the first time the cloning of geranylgeranyl diphosphate synthase gene from T. wilfordii was reported, it lays the foundation for further research of diterpenoids biosynthetic pathway.
Amino Acid Sequence ; Cloning, Molecular ; Farnesyltranstransferase ; chemistry ; genetics ; metabolism ; Molecular Sequence Data ; Phylogeny ; Plant Proteins ; chemistry ; genetics ; metabolism ; Sequence Alignment ; Sequence Homology, Amino Acid ; Tripterygium ; chemistry ; enzymology ; genetics

RecQ is a highly conserved helicase necessary for maintaining genome stability in all organisms. Genome comparison showed that a homologue of RecQ in Deinococcus radiodurans designated as DR1289 is a member of RecQ family with unusual domain arrangement: a helicase domain, an RecQ C-terminal domain, and surprisingly three HRDC domain repeats, whose function, however, remains obscure currently. Using an insertion deletion, we discovered that the DRRecQ mutation causes an increase in gamma radiation, hydroxyurea and mitomycine C and UV sensitivity. Using the shuttle plasmid pRADK, we complemented various domains of the D. radiodurans RecQ (DRRecQ) to the mutant in vivo. Results suggested that both the helicase and helicase-and-RNase-D-C-terminal (HRDC) domains are essential for complementing several phenotypes. The complementation and biochemical function of DRRecQ variants with different domains truncated in vitro suggested that both the helicase and three HRDC domains are necessary for RecQ functions in D. radiodurans, while three HRDC domains have a synergistic effect on the whole function. Our finding leads to the hypothesis that the RecF recombination pathway is likely a primary path of double strand break repair in this well-known radioresistant organism.
Amino Acid Sequence ; Deinococcus ; enzymology ; genetics ; Molecular Sequence Data ; Mutation ; genetics ; Phenotype ; Protein Structure, Tertiary ; RecQ Helicases ; chemistry ; genetics ; metabolism ; Sequence Alignment ; Sequence Homology, Amino Acid

This paper is to show a way of acqusition of the variable region gene of rabbit osteoprotegerin (OPG) and to analyse series. Total RNA was extracted from rabbit tibia, transcripted reversely into cDNA with random primers. The variable region of the OPG gene ampliflied using 5'RACE. Sequencing was confirmed by agarose gel electrophoresis and sequencing analysis. Full length of OPG gene was 1540bp that encoding 400 amino acids. It shared 89% identity with human OPG in whole amino acid sequence and about 85% with rattus norvegicus and other mammal. The OPG sequence of rabbit was obtained by 5'RACE, which could provide a good basis for OPG functional study.
Animals ; Base Sequence ; Molecular Sequence Data ; Osteoprotegerin ; genetics ; Rabbits ; Sequence Homology, Amino Acid

OBJECTIVETo report on a novel HLA-A allele, A*29:49, identified in a Chinese Han population by sequence based typing (SBT).

METHODSA donor from China Marrow Donor Programme (CMDP) was typed with a bi-allelic PCR-SBT kit, and no full matched result was obtained for the HLA-A locus. The novel HLA allele was verified with an allele-specific amplification SBT kit.

RESULTSA novel HLA-A allele was identified, which has differed by one nucleotide from the closest matched allele, HLA-A*29:01:01:01, at position 368(A→T), codon 99 (TAT→TTT), resulting in an amino acid substitution (Y→F). Another allele was verified as A*02:06:01.

CONCLUSIONA novel HLA-A allele was identified and officially named as HLA-A*29:49 by the WHO Nomenclature Committee for Factors of the HLA System.

Alleles ; Amino Acid Substitution ; genetics ; Base Sequence ; China ; HLA-A Antigens ; genetics ; Humans ; Sequence Analysis, DNA ; methods