Human carbonyl reductase. Nucleotide sequence analysis of a cDNA and amino acid sequence of the encoded protein.

The nuclei of mouse spermatozoa contain two protamine variants, mouse protamine 1 (mP1) and mouse protamine 2 (mP2). The amino acid sequence predicted from mP1 cDNAs demonstrates that mP1 is a 50-amino-acid protein with strong homology to other mammalian P1 protamines. Nucleotide sequence analysis of independently isolated, overlapping cDNA clones indicated that mP2 is initially synthesized as a precursor protein which is subsequently processed into the spermatozoan form of mP2. The existence of the mP2 precursor was confirmed by amino acid composition and sequence analysis of the largest of a set of four basic proteins isolated from late-step spermatids whose synthesis is coincident with that of mP1. The sequence of the first 10 amino acids of this protein, mP2 precursor 1, exactly matches that predicted from the nucleotide sequence of cDNA and genomic mP2 clones. The amino acid composition of isolated mP2 precursor 1 very closely matches that predicted from the mP2 cDNA nucleotide sequence. Sequence analysis of the amino terminus of isolated mature mP2 identified the final processing point within the mP2 precursor. These studies demonstrated that mP2 is synthesized as a precursor containing 106 amino acids which is processed into the mature, 63-amino-acid form found in spermatozoa.

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Characteristics of a New Enantioselective Thermostable Dipeptidase from Brevibacillus borstelensis BCS-1 and Its Application to Synthesis of a d-Amino-Acid-Containing Dipeptide

Applied and Environmental Microbiology ◽

10.1128/aem.70.3.1570-1575.2004 ◽

2004 ◽

Vol 70 (3) ◽

pp. 1570-1575 ◽

Cited By ~ 4

Author(s):

Dae Heoun Baek ◽

Jae Jun Song ◽

Seok-Joon Kwon ◽

Chung Park ◽

Chang-Min Jung ◽

...

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Nucleotide Sequence ◽

Amino Acid Sequence ◽

Open Reading Frame ◽

Nucleotide Sequence Analysis ◽

Reading Frame ◽

E Coli ◽

Specificity Constant ◽

Optimal Ph

ABSTRACT A new thermostable dipeptidase gene was cloned from the thermophile Brevibacillus borstelensis BCS-1 by genetic complementation of the d-Glu auxotroph Escherichia coli WM335 on a plate containing d-Ala-d-Glu. Nucleotide sequence analysis revealed that the gene included an open reading frame coding for a 307-amino-acid sequence with an M r of 35,000. The deduced amino acid sequence of the dipeptidase exhibited 52% similarity with the dipeptidase from Listeria monocytogenes. The enzyme was purified to homogeneity from recombinant E. coli WM335 harboring the dipeptidase gene from B. borstelensis BCS-1. Investigation of the enantioselectivity (E) to the P1 and P1′ site of Ala-Ala revealed that the ratio of the specificity constant (k cat /Km ) for l-enantioselectivity to the P1 site of Ala-Ala was 23.4 Ã¯Â¿Â½ 2.2 [E = (k cat /Km ) l,d /(k cat /Km ) d,d ], while the d-enantioselectivity to the P1′ site of Ala-Ala was 16.4 Ã¯Â¿Â½ 0.5 [E = (k cat /Km ) l,d /(k cat /Km ) l,l ] at 55Ã¯Â¿Â½C. The enzyme was stable up to 55Ã¯Â¿Â½C, and the optimal pH and temperature were 8.5 and 65Ã¯Â¿Â½C, respectively. The enzyme was able to hydrolyze l-Asp-d-Ala, l-Asp-d-AlaOMe, Z-d-Ala-d-AlaOBzl, and Z-l-Asp-d-AlaOBzl, yet it could not hydrolyze d-Ala-l-Asp, d-Ala-l-Ala, d-AlaNH2, and l-AlaNH2. The enzyme also exhibited β-lactamase activity similar to that of a human renal dipeptidase. The dipeptidase successfully synthesized the precursor of the dipeptide sweetener Z-l-Asp-d-AlaOBzl.

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Cloning and Sequence Analysis of Gene Encoding Flavonol Synthase from Trung Du Teas Growing in Thai Nguyen

VNU Journal of Science Natural Sciences and Technology ◽

10.25073/2588-1140/vnunst.4474 ◽

2017 ◽

Vol 33 (4) ◽

Author(s):

Hoang Thi Thu Yen ◽

Mai Thi Huyen Trang ◽

Pham Thi Hang ◽

Huynh Thi Thu Hue

Keyword(s):

Amino Acid ◽

Sequence Analysis ◽

Nucleotide Sequence ◽

Amino Acid Sequence ◽

Binding Site ◽

Amino Acid Position ◽

Gene Analysis ◽

Cloning And Sequencing ◽

Gene Encoding ◽

Flavonol Synthase

In this study, we conducted the cloning and sequencing gene encoding FLS from the two green and purple Trung Du tea cultivars. The length of FLS gene is 996 bp, encodes 331 amino acid. Results of FLS gene analysis showed that green and purple Trung Du cultivars has 13 nucleotide variants total as compare with FLS sequence published on Genbank. Nucleotide sequence differences lead to change amino acid sequence of key functional motives in FLS like motif characterizes the 2OG-Fe (II) oxygenase superfamily, the PxxxIRxxx-EQP motif at the N-terminal (18→29) determines the FLS activity, the CPQ/RPxLAL motif) is the binding site of 2-oxoglutarate. How amino acid position changes affect FLS activity need further research. FLS gene isolates are sources for further research to aim elucidating the function of this enzyme.

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