In some embodiments, the present invention provides a protein comprising amino acids in the following sequence L(X).sub.n=14X.sup.3(X).sub.n=1X.sup.1(X).sub.n=1E(X).sub.n=4P(X).sub.n=1NR(X).sub.n=3S(X).sub.n=4D(X).sub.n=2G(X).sub.n=7Y(X).sub.n=4Y (X).sub.n=32-34X.sup.2 (SEQ ID NO: 128), wherein each X independently represents any naturally occurring amino acid residue and n indicates the number of amino acid residues represented by the respective paranthetical at that position, wherein: a) X.sup.1 is selected from the group consisting of S, C, T, M, V, Y, N, P, L, G, Q, A, I, D, W, H, or E, wherein if X.sup.1 is L, H or V, then X.sup.3 is D; and/or b) X.sup.2 is selected from the group consisting of H, L, S or V. In some embodiments, the present invention also provides a protein comprising amino acids in the sequence set forth by SEQ ID NO: 38 or SEQ ID NO: 39, except that: the amino acid at position 406 is an amino acid other than F; and/or the amino acid at position 474 is an amino acid other than N.

A molecular recognition element comprising a target molecule-recognizing portion, and a direct electron transfer-type oxidoreductase linked to the target molecule-recognizing portion.

The present invention relates to improved variants of variants of the Glucose Dehydrogenases (GlucDH) derived from Bacillus subtilis having improved properties in the presence of cNAD as cofactor, to genes encoding such variant GlucDHs, to proteins of such GlucDH variants, and to different applications of these GlucDH variants, particularly for determining concentrations of sugars, especially of glucose, in samples such as bodily fluids, especially blood.

Provided is a process for the preparation of L-methionine in an enzymatic reaction utilizing dimethyl disulfide (DMDS) a precursor of L-methionine, and an organic reducing compound. In the process, methyl mercaptan can be formed by the enzymatic hydrogenolysis of the DMDS.

The invention relates to novel biocatalytic processes comprising the whole cell reduction of dehydrocholic acid (DHCA) compounds, novel 7-hydroxy steroid dehydrogenase mutants, the sequences coding for these enzyme mutants, methods for producing the enzyme mutants and use thereof in enzymatic conversions of cholic acid compounds, and in particular in the production of ursodesoxycholic acid (UDCA); also a subject of the invention are novel methods for the synthesis of UDCA using the enzyme mutants; and in particular a further improved method for producing UDCA using recombinant whole cell biocatalysts.

Disclosed are a gene mining method combining functional sequence and structure simulation, an NADH-preferring phosphinothricin dehydrogenase mutant and an application thereof. The gene mining method comprises the following steps: (1) analyzing a characteristic sequence which an NADH-type glutamate dehydrogenase should have; (2) searching a gene library based on the characteristic sequence; (3) performing clustering analysis and protein structure simulation on genes obtained by the searching; (4) selecting genes that feature high gene aggregation and a protein structure similar to that of the known phosphinothricin dehydrogenase as candidate genes. A wild-type phosphinothricin dehydrogenase with an amino acid sequence as set forth in SEQ ID No.2 derived from Lysinibacillus composti is obtained through the gene mining, and then mutated, and an NADH-preferring phosphinothricin dehydrogenase mutant is screened out, which has a mutation site selected from one of the following: (1) A144G-V375F-M91A; (2) A144G-V345A-M91A; (3) A144G. This mutant enzyme can be used for catalytic reaction with an inexpensive coenzyme NAD.

The present disclosure discloses a production method of Danshensu, belonging to the technical field of bioengineering. The present disclosure constructs a novel genetic engineering strain co-expressed by three enzymes, which can be applied to the production of optically pure 3-(3,4-dihydroxyphenyl)-2-hydroxypropionic acid. All of the (D/L)--hydroxycarboxylic acid dehydrogenase selected by the present disclosure have the characteristics of poor substrate specificity and strong optical specificity, and can produce optically pure D-danshensu and L-danshensu. Further, the production efficiency of the recombinant strain is improved by knocking out or enhancing the expression of a related gene on the E. coli genome to promote substrate transport and reduce product decomposition. The method for producing Danshensu and -ketoglutaric acid by using the transformation of the recombinant strain according to the present disclosure is simple, has easily available raw materials, few impurities, and has good industrial application prospects.

A method for preparing (S)-nicotine by reduction includes conducting a reduction process on an alkene compound as shown in Formula I and/or an iminium cation compound as shown in Formula II, thereby producing (S)-nicotine. The method is simple, safe, reliable, and yields both high purity and high quantities of (S)-nicotine production.

Provided are a recombinant microorganism including a genetic modification that increases a pyruvate, phosphate dikinase activity, a method of producing cellulose using the same, and a method of producing a microorganism having enhanced cellulose productivity.

Methods of cross-linking polypeptide molecules are provided, where such methods include combining a cross-linking agent and polypeptide molecules in a solution under conditions suitable for a cross-linking reaction to occur. Also provided are preparations of cross-linked polypeptide molecules, where the polypeptide molecules are cross-linked by essentially unbranched cross-linking groups of at least 40 contiguous atoms. Further provided are test chemistry matrices and methods of making the same, where the matrices include a redox cofactor, an agent capable of eliciting a change in at least one measurable property of an indicator reagent in the presence of redox equivalents, an indicator reagent, and a preparation of cross-linked polypeptide molecules as described herein. Test elements and methods of using the same to diagnose diseases such as diabetes also are provided, where the test elements include a test chemistry matrix as described herein.