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The synthesis of a novel bifunctional diketopiperazine (DKP) scaffold derived from L-aspartic acid and (S)-2,3-diaminopropionic acid is reported. DKP-1 bears amino and carboxylic acid functionalities in a cis relationship which could be applied to grow peptide sequences.

Searches for homology amongst protein sequences can identify families of related proteins. The AraC/XylS family of regulators is a common positive regulator and is distinguished by an amino acid sequence homology stretching over a 100-residue span, comprising the DNA biding domain of family members. Their regulatory functions include carbon metabolism, pathogenesis and stress response.

Isocitrate dehydrogenase from Thermus aquaticus YT1 harbors a single open reading frame of 1,278 bp, which is preceded by a Shine-Dalgarno ribosome binding site. A terminator-like sequence is located downstream of the open reading frame. The amino acid sequence of this enzyme is highly similar to that of its counterparts from Escherichia coli and Bacillus subtilis, but shares little similarity with the counterpart from T. thermophilus. The cloned gene of isocitrate dehydrogenase is highly expressed in Escherichia coli, and can be purified to homogeneity easily.

The cumD gene, that encodes 2-hydroxy-6-oxo-7-methylocta-2,4-dienoic acid hydrolase, is responsible for the cumene degrading activity of Pseudomonas fluorescens IP01. Three open reading frames, ORF11, ORF12, and ORF13, have been identified in cumD, using polymerase chain reaction technique. The gene organization, size, and homology of corresponding enzymes of the cumD gene cluster are similar to those of the bph gene cluster from Pseudomonas sp. strain LB400 and the tod gene cluster from P. putida F1.

The bacteriocin piscicocin V1a has a molecular mass of 4,416 Da and contains 44 amino acid residues, while piscicocin V1b is a 4,526 Da peptide identical to carnobacteriocin BM1 of Carnobacterium piscicola. Both the bacteriocins contain the consensus YGNGV sequence. Their C-terminal is involved in membrane anchoring and the N-terminal in receptor recognition. The bacteriocins are bactericidal, and inhibit various gram-positive bacteria. Piscicocin V1a is more active than piscicocin V1b.

The enzyme oleamide hydrolase is responsible for the inactivation of neuromodulatory fatty acid amides, bioactive signalling molecules. The protein sequence of the fatty-acid amide hydrolase (FAAH) has similarities with the protein sequence of the various amidase enzyme sequences taken from divergent organisms. These different amidases share a common identifying sequence. The FAAH cDNA transfected COS-7 cells show high activity levels of oleamide hydrolase.

Aconitase is an iron-sulfur (Fe-S) protein with enzymatic properties that acts as an iron-regulatory protein for intracellular iron homeostasis. The 4Fe-4S cluster is sterically free to interact with the substrates to form chelates with carboxyl and hydroxyl groups. The Fe4 site in aconitase functions in enzyme catalysis by delocalizing the electron density in the transition state and reducing the pK(sub a) of a water molecule bound to the metal. The mitochondrial, plant and bacterial aconitase show sequence similarity with an iron regulatory protein.

Enterococcus faecalis INIA 4 produces pure enterocin 4, a bacteriocin, that is antagonistically inactive against gram-negative bacteria. Genetic and chemical characterization of the compound reveals that the primary structure of enterocin 4 is similar to that of the peptide antibiotic AS-48 obtained from Enterococcus faecalis S-48. Enterocin 4 needs an energized membrane for pore formation and a high proton motive force in the cells for its activity.

The genes encoding enzymes involved in the catabolism of isopropylbenzene (IPB) in Psuedomonas sp. strain JR1 have been identified in a cosmid clone consisting of seven open reading frames. The ipbA gene codes for IPB dioxygenase, ipbB codes for 2,3-dihydro-2,3-dihydroxy-IPB dehydrogenase and ipbC codes for 3-isopropylcatechol 2,3-dioxygenase. The amino acid sequence of the clone is similar to that of the proteins involved in biphenyl-degradation in gram-positive and gram-negative bacteria. IPB is the inducer substrate for trichloroethene oxidation in Pseudomonas.

The immunologic properties of the recombinant rat cGMP-inhibited cyclic nucleotide phosphodiesterase (RcGIP1) and human GIP2 (HcGIP2), expressed in NIH 3006 murine fibroblasts and Sf6 insect cells, are similar to that of the native enzymes. The recombinant enzymes have a high cAMP affinity, and are sensitive to cGI PDE inhibitors and cGMP. The N-terminal is necessary for membrane binding of the enzymes. The amino acid sequence of RcGIP1 and HcGIP2 is highly similar in the catalytic regions but dissimilar in the N-terminal regulatory regions.

The sequence of K-12 chromosome in Escherichia coli, which includes a 19-gene cluster responsible for the production of colanic acid, has been determined. The cluster includes genes for GDP-L-fucose synthesis and for the enzyme, GDP-D-mannose 4,6-dehydratase involved in this pathway. The first three genes encode a phosphatase, an outer and an inner membrane lipoprotein, and have homologs in other extracellular polysaccharide gene clusters. These help in the transport of polysaccharide from the cell.

The structural and thermodynamical properties of self complementary duplex decamer having alfa-anomeric nucleotide alfa-T, by 3'-3' and 5'-5' phosphodiester bond, is compared with the unmodified beta-analog. Alfa-T is present in parallel alignment, forming reverse Watson-Crick base pairing in otherwise antiparallel DNA molecule, and causes only local perturbation. Stacking and handedness are unchanged. Sugar ring puckering is S-type, but its amplitude in alfa-T is decreased. Chimeric DNA, having alfa and beta sequences, shows antisense property which has potential in gene therapy.

Phylogenetic analysis of the 16S rRNA of the spirochetes isolated from Ixodes tanuki, I. turdus and I. columnae shows that the spirochetes are genetically distinct from the other known Borrelia strains. The isolates from Ixodes tanuki, I. turdus and I. columnae have been designated as Hk501, Ya501 and Am501 respectively. The isolates have their own tick vectors with enzootic cycles, and are different from each other and the Borrelia species causing Lyme disease. A comparison of the 16S rRNA indicates that Am501 is related to Hk501.

Four promoters from the corynebacterial phi-GA1 phage and 18 promoters from the Sau3A sequences of Corynebacterium glutamicum have been identified by cloning the sequences in the pEKpICm promoter probe vector. The transcriptional start (TS) regions of the promoters have also been identified. The promoters contain conserved sequences in the 35 bp and 10 bp area upstream of the TS region. These sequences are similar to the consensus sequences in Gram-positive and Gram-negative bacteria. The promoters are capable of stimulating the transcription of cat in Escherichia coli.

The levansucrase (lsdA) gene of the gram-negative nitrogen-fixing bacteria, Acetobacter diazotrophicus SRT4, contains ribosome-binding regions, two putative translation initiation codons, and a transcription terminator. Its amino acid sequence specially in the C-terminal region is similar to that of the levansucrases of other Gram-negative bacteria. The gene encodes a 64.9 kDa polypeptide with levansucrase activity. Levansucrase is involved in sucrose metabolism, as a mutation in the lsdA gene disrupts levansucrase activity and the ability to use sucrose as a carbon source.

The cspG gene is a low-temperature-inducible gene found at 22 min in Escherichia coli chromosomes. The gene is a member of the cspA family of genes encoding cold shock proteins. It encodes a protein consisting of 70 amino acids that is 73% identical to CspA and 77% identical to CspB E. coli proteins. The gene sequence of cspG is significantly similar to that of cspA and cspB in the coding regions and the 5'-upstream noncoding regions.

The maoB gene encodes a polypeptide than stimulates the transcription of the monoamine oxidase gene (maoA) in Escherichia coli. Tyramine and the MaoB protein transcriptionally activate maoA by binding to the regulatory region of maoA. The maoB gene is adjacent to the maoA gene in the maoX region of the E. coli chromosome and its expression is controled by catabolic inhibition. The maoB gene has a nucleotide sequence of 903 bp and the MaoB proteins has a molecular mass of 34,619 Da. The amino acid sequence of the MaoB C-terminal is similar to the helix-turn-helix region motif of the AraC family.

The primary immunity region of the Escherichia coli linear plasmid prophage N15 contains the cB gene that is the immunity determinant of N15 and is homologous to lambdoid phage repressors. A mutation in the cB gene prevents the lysogenization of N15 at high temperatures and increases the plasmid copy number of N15 at temperatures that allow lysogenization. The binding of the CB protein to DNA at symmetric 16-bp sites helps in regulating the expression of genes surrounding the cB gene.

CspA and four other small proteins with DNA- and RNA-binding sites constitute the family of dimeric major cold shock protein homologs in the psychrotrophic Bacillus cereus WSBC 10201. The amino acid sequences of the proteins are similar to each other, other prokaryotic cold shock proteins and the cold shock region of Y-box proteins. The CspA and CspE proteins are recovered as dimers with a molecular mass of 15 kDa by gel filtration. The proteins dissociate into their monomers at high salt levels. CspA shows strong expression during growth at low temperature and after cold shock.

The wild-type complementing gene, spsB, and related genes that are necessary for assembly and secretion of the polysaccharide capsule in Sphingomonas strain S88 are present in a multicistronic locus. The genes are also required for the initial transfer of sugar to isoprenylphosphate. The neighboring genes are necessary for the synthesis of dTDP-L-rhamnose, transfer of additional sugars, and secretion of the capsule from the cell. There are two genes that control the secretion of a toxin-like protein.

The 5' terminal region of the msp gene of spirochete Treponema denticola contains an open reading frame of 1,629 bp that encodes the major outer sheath protein (Msp). The encoded peptide contains 543 residues, and its molecular mass is 58,233 Da. It has a prokaryotic signal sequence and a signal peptidase I cleavage site. The Msp expression is lethal for Escherichia coli in the presence of the whole msp gene. The recombinant Msp binds to immobilized laminin and fibronectin. Soluble substrates decrease the binding, while pretreatment with recombinant Msp increases it.

The enteropathogenic Escherichia coli contains the bfp gene cluster that regulates the synthesis of morphologically normal bundle-forming pilus (BFP) filament in deletion mutants. The gene cluster contains 12 adjacent open reading frames that are structurally similar to the IV pilus accessory genes and genes necessary for transformation and protein secretion. A potential replication origin containing genes encoding proteins is present just of the gene cluster. The bfp gene cluster is a conserved feature of enteropathogenic E. coli.

The sodC gene that encodes the copper-zinc superoxide dismutase (CuZnSOD) of Escherichia coli is present at 37.1 min on the chromosome near the lhr and sodB genes. The gene contains a ribosome binding site, and its amino terminal is preceded by a leader group. The amino acid sequence of the gene suggests that it encodes a protein of 15,736.6 Da. The encoded CuZnSOD is secreted into the periplasm probably to defend periplasmic biomolecules from extracytoplasmic superoxides. The enzyme is monomeric and is less stable than other bacterial CuZnSODs.

The IS1301 insertion element of Neisseria meningitidis strains specifically inserts at the 5'-AYTAG-3' site, and the central TA duplicates after the insertion. Most of the IS1301 insertions are found within the least frequently present tetranucleotide of the bacterial genome. An extended palindromic symmetry and the high occurrence of AT tracts around the target site show that DNA secondary structures are involved in target recognition.

The Thr residues of the 45-kilodalton (kDa) glycoprotein of Mycobacterium tuberculosis containing an alpha-D-Man, mannobiose or mannotriose unit are universally O-glycosylated. The glycosylation sites are present in the Pro-rich areas of the N- and C-terminal of the mature 45-kDa glycoprotein. The Pro residues increase glycosylation by increasing the recognition of Thr residues by glycosyltransferase. Glycosylation makes the glycoprotein stiff and extended in conformation. This is probably necessary for targeting glycoproteins to the external environment.

Several human neurological disorders are associated with proteins containing abnormally long runs of glutamine residues. Strikingly, most of these proteins contain two or more additional long runs of amino acids other than glutamine. We screened the current human, mouse, Drosophila, yeast, and Escherichia cold protein sequence data bases and identified all proteins containing multiple Iong homopeptides. This search found multiple long homopeptides in about 12% of Drosophila proteins but in only about 1.7% of human, mouse, and yeast proteins and none among E. cold proteins. Most of these sequences show other unusual sequence features, including multiple charge clusters and excessive counts of homopeptides of length [greater than or equal to] 2 two amino acid residues. Intriguingly, a large majority of the identified Drosophila proteins are essential developmental proteins and, in particular, most play a role in central nervous system development. Almost half of the human and mouse proteins identified are homeotic homologs. The role of long homopeptides in fine-tuning protein conformation for multiple functional activities is discussed. The relative contributions of strand slippage and of dynamic mutation are also addressed. Several new experiments are proposed.

The genes from Pseudomonas fluorescens ST, responsible for the initial steps of styrene degradation, are arranged in a cluster and appear to be encoded by the same DNA strand. Cloning of the genes reveals the presence of monooxygenase, epoxystyrene isomerase, and epoxystyrene reductase activities. The monooxygenase and epoxystyrene isomerase genes are present on the same DNA strand and their expression depends on the pTZ19 lacZp activity. The activity of the epoxystyrene reductase gene depends on an internal promoter.

The membrane protein, aquaporin toad bladder (AQP-TB), from Bufo marinus has structural characteristics that resemble other AQPs. AQP-TB is localized in water channel-containing endosomes and is expressed in tissues such as the urinary bladder, skin, lungs, kidney and brain. Its expression increases by dehydration and chronic antidiuretic hormone stimulation. The expression of AQP-TB in Xenopus laevis oocytes is, however, unable to increase water permeability in the oocytes. This is probably because it is intracellularly sequestrated due to the unique YXRF sequence in the carboxy-terminal.

The fifth membrane-spanning segment and its surroundings of the dopamine D2 receptor have 25 consecutive residues in the binding-site crevice. 13 side chain residues are exposed in the binding-site crevice. The 10 consecutive exposed residues are between Phe189 and Phe198. A side of the alpha-helix formed by the fifth membrane-spanning segment is exposed in the binding-site crevice.

Cyclic nucleotides modulate potassium (K) channel activity in many cells and are thought to act indirectly by inducing channel protein phosphorylation. Herein we report the isolation from rabbit of a gene encoding a K channel (Kcn1) that is specifically activated by cGMP and not by cAMP. Analysis of the deduced amino acid sequence (725 amino acids) indicates that, in addition to a core region that is highly homologous to Shaker K channels, Kcn1 also contains a cysteine-rich region similar to that of ligand-gated ion channels and a cyclic nucleotide-binding region. Northern blot analysis detects gene expression in kidney, aorta, and brain. Kcn1 represents a class of K channels that may be specifically regulated by cGMP and could play an important role in mediating the effects of substances, such as nitric oxide, that increase intracellular cGMP.

We have identified an amino acid sequence in the Drosophila Transformer (Tra) protein that is capable of directing a heterologous protein to nuclear speckles, regions of the nucleus previously shown to contain high concentrations of spliceosomal small nuclear RNAs and splicing factors. This sequence contains a nucleoplasmin-like bipartite nuclear localization signal (NLS) and a repeating arginine/serine (RS) dipeptide sequence adjacent to a short stretch of basic amino acids. Sequence comparisons from a number of other splicing factors that colocalize to nuclear speckles reveal the presence of one or more copies of this motif. We propose a two-step subnuclear localization mechanism for splicing factors. The first step is transport across the nuclear envelope via the nucleoplasmin-like NLS, while the second step is association with components in the speckled domain via the RS dipeptide sequence.

The Bacillus sp. strain LG12 contains the sprA, sprB, sprC, and sprD subtilisin-like protease genes which contain propeptides and signal sequences suggestive of secreted proteins. The SprC and SprD proteases are not related to subtilisin BPN' and other subtilisins. The downstream sprC and sprD genes seem to be transcribed independently while the upstream sprA and sprB genes seem to be a part of the same transcript. The signal sequence of SprB and the mature sequence of SprC contain one cysteine each while SprA and SprD contain no cysteine.

The genes of Pseudomonas pickettii YH105, responsible for the degradation of p-nitrobenzoate, are present on a 43-kb partial MboI fragment. The gene encoding p-nitrobenzoate reductase is present on a 1.4-kb SalI-SphI fragment, while that encoding hydroxylaminolyase is present on a 0.6-kb ApaI-SphI fragment. The two genes are adjacent to each other. The bioreduction of p-nitrobenzoate involves the formation of p-hydroxylaminobenzoate and protocatechuate.

The Lactococcus lactis plasmid pNP40 contains AbiE and AbiF abortive infection phage mechanisms, which are encoded by two open reading frames (ORFs) and one ORF, respectively. The amount of GC in the ORFs encoding AbiE and AbiF is low. The AbiF protein is similar to the AbiD and AbiD1 proteins. AbiE confers partial resistance to phi-712 probably by disrupting the transcription, packaging or release of phage particles. AbiF confers partial resistance to both phi-c2 and phi-712 by suppressing phage replication.

The Tn5467 transposon present in the Thiobacillus ferrooxidans pTF-FC2 plasmid has two 38-bp inverted repeat sequences and open reading frames similar to a glutaredoxin-like protein, a MeR regulatory protein, and a multidrug-resistant membrane transport-like protein. One invert sequence is identical to and the other has a single-base pair mismatch with those of the Tn21 transposase. The transposase and resolvase genes of Tn5467 are biologically inactive. The Tn5467 gene encoding the glutaredoxin-like protein expressed in Escherichia coli complements E. coli thioredoxin mutants.

We have cloned and characterized the Antennapedia (Antp) gene from the grasshopper Schistocerca americana. The Antennapedia protein contains seven blocks of sequence, including the homeodomain, that are conserved in the homologous proteins of other inserts, interspersed with (usually repetitive) sequences unique to each species. There is no similarity between 1.8 kb of 3' untranslated sequence in grasshopper and Drosophila. We examined Antennapedia protein expression in grasshopper using an antibody raised against a grasshopper fusion protein and reexamined its expression in Drosophila using several different antibodies. Early patterns of expression in the two insects are quite different, reflecting differing modes of early development. However, by the germband stage, expression patterns are quite similar, with relatively uniform epithelial expression throughout the thoracic and abdominal segments which later retracts to the thorax. Expression is observed in muscle pioneers, the peripheral nervous system, and the central nervous system (CNS). In the CNS expression is initially limited to a few neurons, but eventually becomes widespread. Both insects show strong expression in certain homologous identified neurons and similar temporal modulation of expression.

The NPLIY sequence of amino acids of the beta-2-adrenergic receptor (beta-2AR) plays an important role in the maintenance of the normal conformation of the receptor. The motif is necessary for the proper binding of the receptor to G-protein and agonist. The NPLIY sequence is a highly conserved motif in the seventh transmembrane domain of the beta-2-AR. Mutations in the most conserved amino acids N, P, and Y in the sequence affect sequestration and many receptor properties.

The binding interactions of streptavidin with linear and cyclic peptides incorporate direct H-bonds, hydrophobic interactions and H-bonds due to water molecules. The linear and disulfide-bridged cyclic peptides have a conserved tripeptide sequence, HPQ. Cyclic peptides containing HPQ bind to streptavidin with a higher affinity. A screening of phage libraries followed by chemical preparation of sequences indicates that a structural-based design can be used along with a chemical process for the design and development of drugs.

Competence for genetic transformation in Streptococcus pneumoniae has been known for three decades to arise in growing cultures at a critical cell density, in response to a secreted pro/ease-sensitive signal. We show that strain CP1200 produces a 17-residue peptide that induces cells of the species to develop competence. The sequence of the peptide was found to be H-Glu-Met-Arg-Leu-Ser-Lys-Phe-Phe-Arg-Asp-Phe-Ile-Leu-Gln-Arg-Lys -Lys-OH. A synthetic peptide of the same sequence was shown to be biologically active in small quantities and to extend the range of conditions suitable for development of competence. Cognate codons in the pneumococcal chromosome indicate that the peptide is made ribosomally. As the gene encodes a prepeptide containing the Gly-Gly consensus processing site found in peptide bacteriocins, the peptide is likely to be exported by a specialized ATP-binding cassette transport protein as is characteristic of these bacteriocins. The hypothesis is presented that this transport protein is encoded by coma, previously shown to be required for elaboration of the pneumococcal competence activator.

The origin recognition complex 1 protein (Orc1p) of Saccharomyces cervisiae is structurally similar to Cdc6p, Cdc18p, and Sir3p. The yeast proteins Cdc6p and Cdc18p control DNA replication. The region of Orc1p that are similar to Cdc6p probably signals the initiation and completion of transcription. Sir3p controls transcription silencing of the mating-type loci. The N-terminal domain regions, that bind to histones and the regions required for protein localization, are similar in Orc1p and Sir3p.

The Epstein-Barr virus-encoded nuclear antigen EBNA-1 gene promoter for the restricted Epstein-Barr virus (EBV) latency program operating in group I Burkitt lymphoma (BL) cell lines was previously identified incorrectly. Here we present evidence from RACE (rapid amplification of cDNA ends) cloning, reverse transcription-PCR, and S1 nuclease analyses, which demonstrates that the EBNA-1 gene promoter in group I BL cell lines is located in the viral BamHI Q fragment, immediately upstream of two low-affinity EBNA-1 binding sites. Transcripts initiated from this promoter, referred to as Qp, have the previously reported Q/U/K exon splicing pattern. Qp is active in group I BL cell lines but not in group III BL cell lines or in EBV immortalized B-lymphoblastoid cell lines. In addition, transient transfection of Qp-driven reporter constructs into both an EBV-negative BL cell line and a group I BL cell line gave rise to correctly initiated transcripts. Inspection of Qp revealed that it is a TATA-less promoter whose architecture is similar to the promoters of housekeeping genes, suggesting that Qp may be a default promoter which ensures EBNA-1 expression in cells that cannot run the full viral latency program. Elucidation of the genetic mechanism responsible for the EBNA-1-restricted program of EBV latency is an essential step in understanding control of viral latency in EBV-associated tumors.

In a search for retinoid X receptor-like molecules in Drosophila, we have identified an additional member of the nuclear receptor superfamily, XR78E/F. In the DNA-binding domain, XR78E/F is closely related to the mammalian receptor TR2, as well as to the nuclear receptors Coup-TF and Seven-up. We demonstrate that XR78E/F binds as a homodimer to direct repeats of the sequence AGGTCA. In transient transfection assays, XR78E/F represses ecdysone signaling in a DNA-binding-dependent fashion. XR78E/F has its highest expression in third-instar larvae and prepupae. These experiments suggest that XR78E/F may play a regulatory role in the transcriptional cascade triggered by the hormone ecdysone in Drosophila.

The adenovirus type 2/5 E1A proteins transform primary baby rat kidney (BRK) cells in cooperation with the activated Ras (T24 ras) oneoprotein. The N-terminal half of E1A (exon 1) is essential for this transformation activity. While the C-terminal half of E1A (exon 2) is dispensable, a region located between residues 225 and 238 of the 243R E1A protein negatively modulates in vitro T24 ras cooperative transformation as well as the tumorigenic potential of ELA/T24 ras-transformed cells. The same C-terminal domain is also required for binding of a cellular 48-kDa phosphoprotein, C-terminal binding protein (CtBP). We have cloned the cDNA for CtBP via yeast two-hybrid interaction cloning. The cDNA encodes a 439-amino acid (48 kDa) protein that specifically interacts with exon 2 in yeast two-hybrid, in vitro protein binding, and in vivo coimmunoprecipitation analyses. This protein requires residues 225-238 of the 243R E1A protein for interaction. The predicted protein sequence of the isolated cDNA is identical to amino acid sequences obtained from peptides prepared from biochemically purified CtBP. Fine mapping of the CtBP-binding domain revealed that a 6-amino acid motif highly conserved among the E1A proteins of various human and animal adenoviruses is required for this interaction. These results suggest that interaction of CtBP with the E1A proteins may play a critical role in adenovirus replication and oncogenic transformation.

The nature of interaction between lactococcal cell envelope-associated proteinase (CEP) and caseins during hydrolysis of kappa-casein is complex. Oligopeptides with amino acid sequences similar to the sequence from residue 98 to 111 and from 153 to 169 of kappa-resin exhibited different susceptibilities to P(sub I) and P(sub III) lactococcal proteinases.

The Drosophila midgut is an excellent system for studying the cell migration, cell-cell communication, and morphogenetic events that occur in organ formation. Genes representative of regulatory gene families common to all animals, including homeotic, TGF[beta], and Wnt genes, play roles in midgut development. To find additional regulators of midgut morphogenesis, we screened a set of genomic deficiencies for midgut phenotypes. Fifteen genomic intervals necessary for proper midgut morphogenesis were identified; three contain genes already known to act in the midgut. Three other genomic regions are required for formation of the endoderm or visceral mesoderm components of the midgut. Nine regions are required for proper formation of the midgut constrictions. The E75 ecdysone-induced gene, which encodes a nuclear receptor superfamily member, is the relevant gene in one region and is essential for proper formation of midgut constrictions. E75 acts downstream of the previously known constriction regulators or in parallel). Temporal hormonal control may therefore work in conjunction with spatial regulation by the homeotic genes in midgut development. Another genomic region is required to activate transcription of the homeotic genes Antp and Scr specifically in visceral mesoderm. The genomic regions identified by this screen provide a map to novel midgut development regulators.

A heptapeptide coded by rat brain cDNA shows properties of an endogenous agonist of the ORL(sub 1) orphan receptor in cell cultures. The peptide suppresses the release of adenylate cyclase in the CHO(ORL1+) cell line and causes hypoglycemia. This neuropeptide contains additional Lys-Arg residues. Structure of this neuropeptide is similar to that of the peptide dynorphin A. Its effect on pain sensitivity is the reverse of the effect of OTL1 suppression. The suggested name for this peptide is nociceptin.

The crystal structure of a light chain protein obtained from the urine of a person with systemic amyloidosis (BRE V(sub L)) is a pseudohexagonal containing six light chain dimers. BRE V(sub L) is a member of the kappa I amyloid proteins and its structure is similar to that of other proteins of this family. However, BRE V(sub L) contains Ile-34, Leu-40 and Tyr-71 amino acids which are not present in other proteins. The amino acids present in the hypervariable region, and the framework area are also different from other proteins.

A study conducted on monocins produced by the bacteria Listeria shows that these monocins are flexible non-contractile bacteriophage-tail-like particles which are probably formed by a defect in the morphogenesis of phages. These monocins produce a lytic enzyme which causes lysis of Escherichia coli cells. The lytic enzyme is an endolysin and is encoded by the cpl2438 gene. The structure of cpl2438 is similar to that of other holin genes.

The cloning and sequencing of the poly-beta-hydroxybutyrate (PHB) biosynthetic genes phaA, phaB and ORF1, in Rhizobium meliloti 41, can be done using heterologus hybridization on a cosmid library. Another gene, phaC, clone is obtained from a R. meliloti PHB-Tn5 mutant. Escherichia coli transducted with these clones expresses phaA and phaB and synthesize PHB. The defect in PHB-mutant of R. meliloti can be removed by the phaC clone. Details of a study conducted on the genes and an analysis of the results are given.