Molecular Weight Polypeptides Research Articles

Combination Effects of Curcumin and Aqueous Extract of Lignosus rhinocerotis Mycelium on Neurite Outgrowth Stimulation Activity in PC-12 Cells

Neurotrophic factors are necessary for neuronal navigation to form viable neuronal networks. These factors are high molecular weight polypeptides that cannot cross the blood brain-barrier. Therefore, small molecules from mushrooms and plants are utilized to maintain neuronal function or up-regulate neurotrophic factors. The present study investigated whether a combination of Lignosus rhinocerotis mycelium aqueous extract and curcumin was more effective than L. rhinocerotis mycelium or curcumin alone in the stimulation of neurite outgrowth of PC-12 cells. The maximum neurite extension for L. rhinocerotis and curcumin was at 21.1% at 20 μg/mL and 29.5% at 10 μg/mL, respectively. Combining 20 μg/mL of L. rhinocerotis with one μg/mL curcumin gave 27.2% neurite extension. This combination was preferred because high concentrations of curcumin were toxic to cells. In the combination, 20 μg/mL of L. rhinocerotis enhanced neurite outgrowth activity at a lower dosage of curcumin at one μg/mL, and produced a comparable percentage of neurite outgrowth stimulation activity to L. rhinocerotis and curcumin alone in PC-12 cells.

The prognostic impact of human leukocyte antigen (HLA) class I antigen abnormalities in salivary gland cancer. A clinicopathological study of 288 cases

To study abnormalities of proteins of the major histocompatibility complex class I in a series of 288 salivary gland carcinomas, and to correlate findings with patients' overall survival (OS). Protein expression of human leukocyte antigen (HLA)-A, heavy chain (HC)-10, β2 -microglobulin, low molecular weight polypeptides (LMP) 2 and 7, transporters associated with antigen processing (TAP) 1 and 2, calnexin, calreticulin, endoplasmic reticulum (ER) p57 and tapasin was evaluated by immunohistochemistry and semiquantitatively analyzed. As compared with normal salivary gland tissue, HLA-A, LMP7, TAP2 and HLA class I were significantly down-regulated in salivary gland carcinomas, whereas β2 -microglobulin, calnexin, LMP2, and TAP1 were upregulated. Expression of calreticulin, ERp57 and tapasin was unaltered. In univariate Kaplan-Meier analyses, low expression of LMP7 (P = 0.005) and high expression of β2 -microglobulin (P = 0.028), HLA-A (P < 0.001), TAP1 (P = 0.01), and tapasin (P < 0.001) were significantly associated with shorter OS. In multivariate analysis incorporating tumour stage, nodal/distant metastasis, and grade, HLA-A (P = 0.014), LMP7 (P = 0.033), and tapasin (P = 0.024), as well as distant metastasis (P = 0.012) and high tumour grade (P < 0.001), remained statistically significant. The prognostic influence of up-regulated HLA-A and tapasin and down-regulated LMP7 may provide a rationale for targeting these specific components of the antigen processing and presentation pathway in salivary gland carcinomas.

The N and C Termini of ZO-1 Are Surrounded by Distinct Proteins and Functional Protein Networks

Biotin ligase tagging with ZO-1 was applied to identify a more complete tight junction proteome. Identical but also different proteins and functional networks were identified near the N and C ends of ZO-1. The ends of ZO-1 are embedded in different functional subcompartments of the tight junction. Biotin tagging with ZO-1 expands the tight junction proteome and defines subcompartments of the junction. The proteins and functional protein networks of the tight junction remain incompletely defined. Among the currently known proteins are barrier-forming proteins like occludin and the claudin family; scaffolding proteins like ZO-1; and some cytoskeletal, signaling, and cell polarity proteins. To define a more complete list of proteins and infer their functional implications, we identified the proteins that are within molecular dimensions of ZO-1 by fusing biotin ligase to either its N or C terminus, expressing these fusion proteins in Madin-Darby canine kidney epithelial cells, and purifying and identifying the resulting biotinylated proteins by mass spectrometry. Of a predicted proteome of ∼9000, we identified more than 400 proteins tagged by biotin ligase fused to ZO-1, with both identical and distinct proteins near the N- and C-terminal ends. Those proximal to the N terminus were enriched in transmembrane tight junction proteins, and those proximal to the C terminus were enriched in cytoskeletal proteins. We also identified many unexpected but easily rationalized proteins and verified partial colocalization of three of these proteins with ZO-1 as examples. In addition, functional networks of interacting proteins were tagged, such as the basolateral but not apical polarity network. These results provide a rich inventory of proteins and potential novel insights into functions and protein networks that should catalyze further understanding of tight junction biology. Unexpectedly, the technique demonstrates high spatial resolution, which could be generally applied to defining other subcellular protein compartmentalization.

Soluble, Clickable Polypeptides from Azide-Containing N-Carboxyanhydride Monomers.

We report a method for the synthesis of soluble, well-defined, azide-functionalized polypeptides via living polymerization of new azide-containing amino acid N-carboxyanhydride (NCA) monomers. Homo and diblock azidopolypeptides were prepared with controlled segment lengths using (PMe3)4Co initiator and were subsequently modified by reaction with functional alkyne reagents. The azide groups were found to be quantitatively converted to the corresponding triazole derivatives, and the functionalized polymers were obtained in high yield. This methodology provides a facile and straightforward method for preparation of functional and side-chain reactive, high molecular weight polypeptides.

Physicochemical properties of protease‐treated rice flour

AbstractThe physicochemical properties of rice flour treated with protease (Protease‐RF) and a conventional alkali steeping method (Alkali‐RF) were compared with native flour. The physical properties of flour gels were assessed by rapid visco analyzer, texture analysis, and rheology with reference to their composition and impact on their starch structures by the two treatment methods. Alkali‐RF exhibited shorter pasting time to peak with higher breakdown but lower setback. However, the textural parameters of both treatments were not significantly different (p &gt; 0.05). The storage modulus for both treatments increased to a greater extent was compared to native flour. Low‐MW polypeptides (5–30 kDa) had less effect on gel‐forming properties, since similar texture qualities were obtained either in their presence or absence. The granule‐bound SS or GBSS (58–60 kDa) had less effect since it could not be removed either by proteases or alkali. The high molecular weight polypeptides (&gt;77 kDa), which were partly removed either by alkali or protease treatments, played an important role in impairing the gel‐forming property of rice flour. Textural quality was observed to improve after their removal, compared to native flour.

Effects of molecular weight on thermal responsive property of pegylated poly-l-glutamates

We investigated the ring opening polymerization (ROP) of di- and tri-ethylene glycol monomethyl ether functionalized L-glutamate N-carboxyanhydrides (NCAs) using hexamethyldisilazane (HMDS) as primary initiator and 1,5,7-triazabicyclo-[4.4.0]dec-5-ene (TBD) as co-initiator. The binary initiator system afforded a living ROP for these pegylated NCAs, and a series of homopolypeptides with controlled molecular weight (MW) and low polydispersity were obtained. We then systematically studied the helical content and clouding point (CP) dependence on polypeptide MW using circular dichroism (CD) spectroscopy and turbidity measurements, respectively. We found that the helical content of both homopolypeptides increased with MW, but the triethylene glycol functionalized poly-L-glutamate (poly-L-EG3Glu) intended to form more stable α-helical structure than diethylene glycol functionalized counterpart (poly-L-EG2Glu) at similar MW. Accordingly, the CP of poly-L-EG2Glu with known end group has strong dependence on its helical content, which is essentially determined by MW. Our results suggested that the thermal responsive properties of these unique pegylated poly-L-glutamates not only rely on their chemical structure but also on their secondary structures, which is different from conventional thermal responsive polymers.

Determination of copolymerisation characteristics in the N-carboxy anhydride polymerisation of two amino acids

Polypeptides are increasingly used as components for biomedical materials. Based on the variety of functional groups and the inherent biocompatibility presented by natural amino acids, the potential functionality offered by polypeptides is considerable and methods based on NCA monomers have been developed to readily access polypeptides of high molecular weight synthetically. Despite some isolated examples of the functionality of random synthetic copolypeptides (e.g., the drug glatiramer acetate), applications of synthetic copolypeptides are thus far mainly restricted to block-polymers because of poor control over the random amino acid NCA polymerisation. This restricted use of random copolypeptides is in large parts due to the inability to monitor the kinetics of the individual monomers, an aspect crucial to understanding and controlling the copolymerisations. Here, a method is presented that allows monitoring of the consumption of two model NCAs, Glu(Bzl)-NCA and Lys(Z)-NCA. This procedure makes kinetic data of the monomer consumption in an NCA copolymerisation accessible for the first time and shows how the different reactivities of the two NCAs in binary mixtures of various monomer ratios affect the composition of the copolymer over time.

The degradation behavior of silk fibroin derived from different ionic liquid solvents

Establishing an appropriate degradation rate is critical for tissue engineering scaffolds. In this study, the degradation rate of silk fibroin three-dimensional scaffolds was regulated by changing the molecular weight (MW) of the silk fibroin. The solubility of silk fibroin depends primarily on the ionic ability of the slovent to dissolve silk fibroin, therefore, we regulated the MW of the silk fibroin using LiBr, Ca(NO3)2 and CaCl2 to dissolve the silk fibers. SDS-PAGE analysis showed that the MW of the CaCl2-derived silk fibroin was lower than the MW produced using LiBr and Ca(NO3)2. In vitro and in vivo degradation results showed that the scaffolds prepared by low-MW silk fibroin were more rapidly degraded. Furthermore, FTIR and amino acid analysis suggested that the amorphous regions were preferentially degraded by Collagenase IA, while the SDS-PAGE and amino acid analysis indicated that the scaffolds were degraded into polypeptides (mainly at 10-30 kDa) and amino acids. Because the CaCl2-derived scaffolds contained abundant low MW polypeptides, inter-intramolecular entanglement and traversing of molecular chains in the crystallites reduced, which resulted in rapid degradation. The in vivo degradation results suggested that the degradation rate of the CaCl2-derived scaffolds was better matched to dermis regeneration, indicating that the degradation rate of silk fibroin can be effectively regulated by changing the MW to achieve a suitable dermal tissue regeneration rate.

Structural and dynamical properties of KTS‐disintegrins: A comparison between Obtustatin and Lebestatin

Obtustatin and Lebestatin are lysine-threonine-serine (KTS)-disintegrins, which are a family of low molecular weight polypeptides present in many viperidae venoms and are potent and specific inhibitors of collagen-binding integrins. The integrin binding loop, harboring the (21)KTS(23) motif, and the C-terminal tail are known to be responsible for the selective binding to the α1β1 integrin. Despite a very high sequence homology (only two mutations are present in Lebestatin relative to Obtustatin, namely R24L and S38L), Lebestatin exhibits a higher inhibitory effect than Obtustatin on cell adhesion and cell migration to collagens I and IV. Here we show, by means of molecular dynamics simulations of the two polypeptides in aqueous solution, that Lebestatin possesses a higher flexibility of the C-terminal tail and a greater solvent accessibility of the integrin binding loop than Obtustatin. It may be hypothesized that these properties may contribute to the higher binding-affinity of Lebestatin to its biological partner.

Genome-wide identification of rice class I metallothionein gene: tissue expression patterns and induction in response to heavy metal stress

Metallothioneins (MTs) are members of a family of cysteine-rich low molecular weight polypeptides which play an important role in heavy metal detoxification and homeostasis of intracellular metal ions in plant. Though MT genes from some selected plants have been characterized with respect to their protein sequences, kinetic properties and tissue-specific localization, no detailed study has been carried out in rice. Here, we present genome-wide identification, structural and expression analyses of rice MT gene family. Our analysis suggests presence of 11 class I MT genes in rice genome (Release 7 of the MSU Rice Genome Annotation Project) which are differentially expressed during growth and development, in various tissues and during biotic and abiotic stresses. Our analyses suggest that class I MT proteins in rice differ in tissue localization as well as in heavy metal coordination chemistry. We also suggest that some MTs have a predominant role in detoxification of As (V) in arsenic-tolerant rice cultivars. Our analysis suggests that apart from transcriptional regulation, post-transcriptional alternative splicing in some members of this family takes place during growth and development, in various tissues and during biotic and abiotic stresses.

Quantification of rumen undegradable protein fractions of conventional and non conventional protein supplements by SDS-PAGE

Conventional [solvent extracted GNC and mechanically extracted mustard cake (MC)], and non-conventional protein supplements [machanically extracted castor oilseed cake (COSC), un-decorticated solvent extracted neem seed cake (NSC) and corn gluten meal (CGM)] before and after rumen incubations for different intervals were subjected to sequential fractionation into globulin, albumin, prolamin and glutelins on the basis of solubility. The polypeptides in globulin, prolamin and glutelin fraction of groundnut cake with molecular weight 35, 15, 16 and 19 KDA, respectively, were highly resistant to microbial degradation even after 24h or rumen incubation. The degradation pattern of mustard cake revealed that subunits of globulin, prolamin and glutelins with MW of 14–33, 14 and 31 KDA, respectively, were highly resistant to microbial degradation. In NSC subunits with MW 124 (in globulin), 30 (in albumin), 66 (in prolamin) and 54 kDa (in glutelin) were resistant to microbial degradation. The subunits in prolamin fraction of CGM with MW 18, 24 and 43 kDa and that in glutelin fraction with MW of 22 and 60 kDa were found to be highly resistant to microbial degradation. The results conclusively revealed that in majority of the cases, the low molecular weight polypeptides in the tested protein supplements showed resistance to rumen microbial fermentation, even after 48h of rumen incubation.

Optimized PEF treatment for antioxidant polypeptides with MW 10–30 kDa and preliminary analysis of structure change

Antioxidant polypeptides of molecular weight (MW) ranging from 10 to 30kDa were produced from egg-white protein powder by enzyme hydrolysis and ultrafiltration (UF). Ferric reducing antioxidant potential (FRAP) value (mmol Fe2+/g) was used to evaluate the antioxidant activity. One-factor-at-a-time (OFAT) tests and Box–Behnken design (BBD) of response surface methodology (RSM) were used to investigate the effect of pulsed electric field (PEF) treatment parameters on antioxidant activity of polypeptides. The optimal conditions were as follows: concentration 8mg/mL, electric field intensity 10kV/cm, and pulse frequency 2000Hz, under which, the FRAP value increased 44.23%, compared to the antioxidant activity of the polypeptides without PEF treatment. Both near-infrared spectroscopy (NIR) and mid-infrared spectroscopy (MIR) were used to analyze the change of functional groups.

An Overview of Molecular and Cellular Mechanisms Associated with Porcine Pregnancy Success or Failure

Prenatal mortality remains one of the major constraints for the commercial pig industry in North America. Twenty to thirty per cent of the conceptuses are lost early in gestation and an additional 10-15% is lost by mid-to-late gestation. Research over the last two decades has provided critical insights into how uterine capacity, placental efficiency, genetics, environment, nutrition and immune mechanisms impact successful conceptus growth; however, the exact cause and effect relationship in the context of foetal loss has yet to be determined. Similar to other mammalian species such as the human, mouse, rat, and primates, immune cell enrichment occurs at the porcine maternal-foetal interface during the window of conceptus attachment. However, unlike other species, immune cells are solely recruited by conceptus-derived signals. As pigs have epitheliochorial placentae where maternal and foetal tissue layers are separate, it provides an ideal model to study immune cell interactions with foetal trophoblasts. Our research is focused on the immune-angiogenesis axis during porcine pregnancy. It is well established that immune cells are recruited to the maternal-foetal interface, but their pregnancy specific functions and how the local milieu affects angiogenesis and inflammation at the site of foetal arrest remain unknown. Through a better understanding of how immune cells modulate crosstalk between the conceptus and the mother, it might be possible to therapeutically target immune cells and/or their products to reduce foetal loss. In this review, we provide evidence from the literature and from our own work into the immunological factors associated with porcine foetal loss.

Study on Enzymatic Hydrolysis into Low Molecular Weight Polypeptides with Microwave Heating

Using amino nitrogen content ( AN for short ) as standards, the conditions of low molecular weight polypeptides with three kinds of enzymes hydrolysis as well as the sequence and way of adding enzymes with microwave heating was found in this paper, which was examined by fluorescence analysis method, seperated by Sephadex G-50. The result shows that three kinds of enzymes hydrolysis were prefer to one enzyme obviously, amino nitrogen was higher for 2813.4 mg/L, the relative molecular mass of soybean polypeptides was mostly below 1000 D. Soybean polypeptide was well tested and seperated by Sephadex G-50 and fluorescence analysis method.

Association of LMP/TAP Gene Polymorphisms with Tuberculosis Susceptibility in Li Population in China

BackgroundTuberculosis (TB) is a contagious disease affected by multiple genetic and environmental factors. Several association studies have suggested that cellular immune response is vital for controlling and preventing of tuberculosis infection. Low molecular weight polypeptides (LMPs) and transporters with antigen processing (TAPs) are the main molecules in the processing and presentation pathway for intracellular antigens. This study was performed to elucidate whether these antigen-processing genes (LMP/TAP) polymorphisms could be associated with the risk of tuberculosis infection in China.Methodology/Principal FindingsWe recruited 205 active pulmonary tuberculosis patients and 217 normal controls from Li population for this study. Four polymorphisms of LMP/TAP genes were determined by PCR-RFLP assay and haplotypes were constructed by software PHASE 1.0. Of the total four polymorphisms, genotype frequencies of LMP7 AA homozygote and CA heterozygote were significantly greater among cases compared to controls, with odds ratio of 3.77 (95% CI: 1.60–8.89; P = 0.002) and 2.97 (95% CI: 1.80–4.90; P<0.0001), respectively. The genotypes of TAP1-2 GG homozygote and AG heterozygote were more frequent in subjects with TB than in controls, with odds ratio of 3.94 (95% CI: 1.82–8.53; P = 0.001) and 2.87 (95% CI: 1.75–4.71; P<0.0001), respectively. Similarly, we found that haplotype B which carried LMP7 and TAP1-2 variations significantly increased the susceptibility to TB (OR = 3.674, 95% CI: 2.254–5.988; P<0.0001). Moreover, it is noteworthy that the homozygote of wild haplotype A (A/A) may be a strong protection for TB infection.ConclusionsOur findings suggested that LMP/TAP gene polymorphisms might be risk factors for TB infection among Li population in China.

Association of antigen processing machinery and HLA class I defects with clinicopathological outcome in laryngeal squamous cell carcinoma

To investigate the role of antigen-processing machinery (APM) component defects in HLA class I antigen down-regulation in laryngeal squamous cell carcinoma (SCC) and to assess the clinical significance of these defects. Fifty-one formalin-fixed, paraffin-embedded SCC specimens were examined for the expressions of APM component transporter associated with antigen processing (TAP1) and low molecular weight polypeptide (LMP-7) and HLA class I antigen by immunohistochemistry. HLA class I antigens, TAP-1 and LMP-7 expressions were down-regulated in 56.9% (29/51), 39.2% (20/51) and 45.1% (23/51) of the tested specimens respectively, whereas HLA class I antigens, TAP-1 and LMP-7 expressions lost in 21.6% (11/51), 33.3% (17/51) and 27.5% (14/51) of the tested specimens respectively. TAP-1 and LMP-7 expressions were significantly correlated with HLA class I antigen expression (r=0.460, P<0.05 and r=0.685, P<0.05, respectively). HLA class I antigens down-regulation was significantly correlated with T stage (χ2=8.61, P<0.05). Both TAP-1 and LMP-7 down-regulations were significantly correlated with T stage (χ2 values were 9.72 and 8.97 respectively, P<0.05) and TNM stage (χ2 values were 9.18 and 7.70 respectively, P<0.05). TAP-1, LMP-7 and HLA class I antigen down-regulations were significantly associated with reduced patients' overall survival (P<0.05) and disease-free survival (P<0.05). Multivariate analysis showed lymph node metastasis, recurrence and HLA class I antigen down-regulation were unfavorable prognostic factors (P<0.05). Down-regulated expressions of HLA class I antigen and APM component TAP-1 and LMP-7 occur frequently in laryngeal squamous cell carcinoma, by which cancer cells could avoid immune surveillance, while HLA class I antigen down-regulation is a major contributing factor to tumour progression and mortality.

Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and random amplified polymorphic DNA (RAPD) based genetic variation studies in eri silkworm (Samia cynthia ricini Lepidoptera: Saturniidae)

Four strains of eri, Samia cynthia ricini Lepidoptera: Saturniidae that can be identified morphologically and maintained at North East Institute of Science and Technology, Jorhat were characterized based on their protein profile by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and DNA by random amplified polymorphic DNA (RAPD) technique. Fiber yield was highest in Gs strain. SDS-PAGE profile showed 11 prominent bands in the strains with molecular weight ranging from 35 to 200 kDa together with 28 minor bands with molecular weight ranging from 33 to 210 kDa. Two polypeptides of molecular weight 90 and 110 kDa were absent in both Y and Ys. Eight random primers and one universal primer used for RAPD analysis generated a total of 79 bands, of which 49 were polymorphic. In both SDS-PAGE and RAPD, the UPGMA based dendrogram showed two clusters: cluster 1 included Gs and G, whereas Y and Ys was grouped in cluster 2 by SDS-PAGE analysis but RAPD analysis grouped Ys and G in cluster 1 and Gs and Y in cluster 2. The range of genetic diversity observed among the strains affirms the potentiality of RAPD technique for identification and selection of distant parents for silkworm hybridization for high silk yield. Key words: Genetic variation, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), random amplified polymorphic DNA (RAPD), silkworm, cocoon.

Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and random amplified polymorphic DNA (RAPD) based genetic variation studies in eri silkworm (Samia cynthia ricini Lepidoptera: Saturniidae)

Four strains of eri, Samia cynthia ricini Lepidoptera: Saturniidae that can be identified morphologically and maintained at North East Institute of Science and Technology, Jorhat were characterized based on their protein profile by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and DNA by random amplified polymorphic DNA (RAPD) technique. Fiber yield was highest in Gs strain. SDS-PAGE profile showed 11 prominent bands in the strains with molecular weight ranging from 35 to 200 kDa together with 28 minor bands with molecular weight ranging from 33 to 210 kDa. Two polypeptides of molecular weight 90 and 110 kDa were absent in both Y and Ys. Eight random primers and one universal primer used for RAPD analysis generated a total of 79 bands, of which 49 were polymorphic. In both SDS-PAGE and RAPD, the UPGMA based dendrogram showed two clusters: cluster 1 included Gs and G, whereas Y and Ys was grouped in cluster 2 by SDS-PAGE analysis but RAPD analysis grouped Ys and G in cluster 1 and Gs and Y in cluster 2. The range of genetic diversity observed among the strains affirms the potentiality of RAPD technique for identification and selection of distant parents for silkworm hybridization for high silk yield. Key words: Genetic variation, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), random amplified polymorphic DNA (RAPD), silkworm, cocoon.

Proteomic Analysis of Decellularized Tissue Engineered Laryngeal‐Tracheal Scaffolds

Objective: The clinical success of a fully tissue-engineered tracheal transplant has indicated that there may be more to using decellularized tissue as a scaffold construct. It has been hypothesized that remnant polypeptides reside in these matrices. We sought to determine the proteome profile of a decellularized laryngeal-tracheal scaffold construct. Method: A laryngeal-tracheal construct was fabricated using standard decellularization protocols and underwent immunohistochemistry, electron microscopy, biomechanical analysis, and qPCR for total DNA content. Samples from anatomical subsites were prepared for proteomic analysis. Tandem mass-spectrometry (LC-MS/MS) was used to identify peptide sequences and validated using multicolor immunohistochemistry and western blotting. Results: Decellularization of laryngea-tracheal scaffold airway construct effectively removed cells, MHC components, and DNA while maintaining similar biomechanical properties to native (nondecellularized) tissue. We identified variable expression of polypeptides in the anatomical subsites of the airway scaffold construct. A minimum core set of polypeptides was identified with a subset of proteins with putative roles beyond structural integrity. Of particular interest were small molecular weight polypeptides known to have significant roles in epithelialization and angiogenesis. Conclusion: We demonstrate that mass spectrometry can be used as a tool to accurately identify residual proteins in a laryngeal-tracheal scaffold. The identification of signaling proteins may be of crucial importance in designing the next generation of “intelligent” off-the-shelf scaffolds.

Layer-by-Layer Assembled Titania Tubular Nanostructures at Different Assembly Conditions

Layer-by-layer (LbL) deposition of poly(L-lysine) (PLL) dissolved in different solutions and a water-soluble titania precursor, titanium(IV) bis(ammonium lactate) dihydroxide (TiBALDH) to form multilayer films on the wall of polycarbonate (PC) membrane pores was performed to prepare nanostructured titania-PLL composite and pure anatase and rutile titania tubes. A battery of analytical techniques was utilized to characterize and compare the structures, crystal phases, and photocatalytic properties of the titania tubes. In different solutions conditions, PLL which adopts secondary conformations (i.e., alpha-helix and random coil) and has varying interactions with different counterions (i.e., chloride and phosphate ions) can influence PLL/TiBALDH deposition and, in turn, results in the titania materials with different nanostructures and phtocatalytic properties. The influence of LbL assembly condition, deposition cycle, and polypeptide molecular weight on photocatalytic properties of resultant anatase titania tubes were further explored and these materials are promising photocatalyst with the advantage of easily handling and recycling. This reported approach may provide a facile and general way to prepare organic-inorganic composite and other inorganic materials with different compositions, structures, and properties for various applications.