Abstract: Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in medium comprising xylose and acetate.

Abstract: Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas strains further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in mixed-sugars medium comprising xylose, and, in particular, in the presence of acetate.

Abstract: Protein engineered CrtO ketolases isolated from Rhodococcus erythropolis AN12 are provided having increased carotenoid ketolase activity. Methods using the present CrtO ketolases are also provided for increasing ketocarotenoid production in suitable production hosts.

Abstract: CrtW carotenoid ketolases are provided that are useful for the production of astaxanthin and other cyclic ketocarotenoids. The mutant ketolase genes of the present invention encode polypeptides characterized by an improvement in astaxanthin synthesis activity when converting cyclic hydroxylated carotenoid intermediates into astaxanthin. Expression of the mutant carotenoid ketolases in heterologous hosts enabled increased production of astaxanthin relative to the Sphingomonas melonis DC18 CrtW.

Abstract: Mutations in chromosomal genes have been identified that affect plasmid copy number in plasmids that are anti-sense RNA regulated such as the pMB1-derived and p15A-derived plasmids.

Abstract: A carotenogenic biosynthetic gene cluster has been isolated from Panteoa stewartii strain DC413, wherein the genetic organization of the cluster is crtE-idi-crtX-crtY-crtI-crtB-crtZ. The genes contained within this cluster encode geranylgeranyl pyrophosphate (GGPP) synthetase (CrtE), isopentenyl pyrophosphate isomerase (Idi), zeaxanthin glucosyl transferase (CrtX), lycopene cyclase (CrtY), phytoene desaturase (CrtI), phytoene synthase (CrtB), and ?-carotene hydroxylase (CrtZ). The gene cluster, genes and their products are useful for the conversion of farnesyl pyrophosphate to carotenoids. Vectors containing those DNA segments, host cells containing the vectors and methods for producing those enzymes by recombinant DNA technology in transformed host organisms are disclosed.

Abstract: CrtW carotenoid ketolases are provided that are useful for the production of astaxanthin and other cyclic ketocarotenoids. The mutant ketolase genes of the present invention encode polypeptides characterized by an improvement in astaxanthin synthesis activity when converting cyclic hydroxylated carotenoid intermediates into astaxanthin. Expression of the mutant carotenoid ketolases in heterologous hosts enabled increased production of astaxanthin relative to the Sphingomonas melonis DC18 CrtW.

Abstract: Novel CrtW carotenoid ketolase are provided that are useful for the production of ketocarotenoids. The ketolases genes of the present invention exhibit low homology in comparison to other CrtW ketolases previously reported. Expression of the carotenoid ketolases in heterologous hosts enabled production of canthaxanthin and astaxanthin. Coexpression experiments using divergent crtW genes resulted in increased production of the desired ketocarotenoids.

Abstract: The present invention describes a mutant plasmid replication control region having the ability to convey a phenotype of altered plasmid copy number to the plasmid on which it resides. The mutant replication control region is based on a similar region isolated from the pBBR1 plasmid family. Plasmids containing this replication control region cannot be classed as belonging to any known incompatibility group and thus may co-exist with a broad range of other plasmids in a single host.

Abstract: Mutations in genes having no direct relationship to the carotenoid biosynthetic pathway have been found to increase carbon flux through that pathway. Complete disruption in the deaD, mreC, and yfhE genes were effective. Additionally where genes of the lower carotenoid pathway reside on a plasmid having either a p15A or pMB1 replicon, mutations in the thrS, rspA, rpoC, yjeR, and rhoL were found effective.

Abstract: Methanotrophic bacterial strains are provided that have been optimized for the production of carotenoid compounds through the down-regulation of one or more of the crtN1, ald, crtN2 and crtN3 genes of the carotenoid biosynthetic pathway. The resulting strains lack pigmented C30 carotenoid compounds, and show an increase in the production of C40 carotenoids. The use of the optimized host strains for the production of the C40 carotenoids canthaxanthin and astaxanthin is also described.

Abstract: A method for the production of aryl-carotenoids is provided through bioconversion of cyclic carotenoids having at least one ?-ionone ring. Expression of a heterologous gene encoding a carotene desaturase (crtU) enzyme in a host cell that produces a suitable cyclic carotenoid substrate effect the production of aryl carotenoids.

Abstract: Genes encoding bacterial oxygen binding proteins are provided. Recombinant expression of at least one of the present bacterial hemoglobin genes increased the growth characteristics and/or carotenoid production levels in microbial host cells grown under microaerobic conditions.

Abstract: A method for the in vivo bioconversion of cyclic carotenes having a ?-ionone ring to the corresponding aryl carotene is provided. Gram negative host cells expressing a heterologous, codon-optimized gene encoding a carotene desaturase are grown in the presence of a suitable cyclic carotene substrate to effect the production of aromatic carotenoids.

Abstract: Genes encoding bacterial oxygen binding proteins are provided. Recombinant expression of at least one of the present bacterial hemoglobin genes increased the growth characteristics and/or carotenoid production levels in microbial host cells grown under microaerobic conditions.

Abstract: Genes isolated from Methylomonas sp. 16a have been determined to play a role in the carotenoid biosynthetic pathway. Specifically, crtN2 gene has the ability to produce omega-aldehyde functional groups on carotenogenic substrates, while the ald gene produced omega carboxyl functional groups. These genes will be useful for production of high levels of functionalized carotenoid compounds, especially those produced in microorganisms which metabolize single carbon substrates.

Abstract: The present invention provides methods to engineer microorganisms for the production of C30-aldehyde carotenoids. Specifically, various combinations of crtM, sqs, crtN and crtN2 genes from Staphylococcus aureus and Methylomonas sp. 16a can be co-expressed in transformant hosts, leading to the production of diaponeurosporene monoaldehyde, diapocarotene monoaldehyde, and/or diapocarotene dialdehyde. In a preferred embodiment, the genetically engineered pathway is introduced into a strain of Escherichia coli that has been engineered for the expression of carotenoids, and the C30-carotenoid product is diapocarotene dialdehyde.

Abstract: A novel CrtZ carotenoid hydroxylase, isolated from Brevundimonas vesicularis DC263, is provided that is useful for the production of hydroxylated carotenoids. Additionally, a previously identified hypothetical protein from Novosphingobium aromaticivorans has found to have carotenoid hydroxylase activity. Both hydroxylase genes exhibit low homology in comparison to other CrtZ hydroxylases previously reported. Expression of the hydroxylases in heterologous host cells enabled production of hydroxylated carotenoids.

Abstract: Protein engineered nucleic acid fragments encoding a CrtO ketolase and a CrtZ hydroxylase are provided with increased astaxanthin synthesis activity. Methods using the present nucleic acid fragments are also provided for increasing or altering astaxanthin production in suitable production hosts.

Abstract: A ketolase gene has been isolated from Rhodococcus erythropolis AN12 strain encoding a carotenoid modification enzyme of the carotenoid biosynthetic pathway. The gene and gene product are the first isolated from a Rhodococcus strain. Six conserved amino acid motifs have been identified as the characteristic of this type of ketolase enzymes. The gene and gene product of the present invention may be used in a variety of ways for the production of keto-carotenoid compounds in a variety of organisms.